Best computer for navigation. That’s not a Garmin.

If in doubt ask DC Rainmaker...box fresh unit may be the one to look at:

https://www.dcrainmaker.com/2019/05/wahoo-element-roam-cycling-gps-in-de...

Another vote for the Bolt - don't often use the turn by turn directions as I found that doesn't always pop up in time, but the map view is fine and it's easy to zoom in and out if you need more detail or if it's a complicated looking junction. Only issue is that you can't move the map around, so if you go off route it's not easy to work out where you are and how to navigate back so that's when you need Google maps. 

Otherwise battery life, accuracy etc are great and love the app interface. Really easy to add routes and manage just through your phone rather than having to boot up the laptop. 

Lezyne Mega XL .... I've got one... decent enough navigation... too me through France and Belgium...maps onboard with arrows to follow and turn by turn guides....usual hook up to many sensors bluetooth and ANT+ from all makes...di2 and Etap etc and power meters if you are into that stuff....claimed 48hr battery... and I still hadn't used 1/4 battery in 2 days use... like on for 8hrs a day... Maps are easy enough to create/download and can cover a fair whack for little memory.... 

Wahoo Elemnt here, and very very happy with it.  You can do route planning from the app and it will load via bluetooth straight on to the unit.  I do this rarely though, as I prefer to plan routes on the ridewithgps site.  However it is handy on one of those exploring type bike rides to know you can open the app, and have the unit then direct you back home.

I was very keen to get away from Garmin, and I have no desire to move away from Wahoo.

I've got a Lezyne Super GPS now largely superseded by the Mega GPS. It's not perfect as it sometimes doesn't want to talk to my phone, but 90% of the time it works as intended. Battery life is well over 15 hours and it offers turn by turn instructions as well as breadcrumb navigation. The Mega has the benefit of offline map storage and displays the map under the route rather than a just a black line to follow.

I've used Garmin Forerunners for about 10 years, with very little problem.  The first one became unresponsive about 2.5 years after I got it, I told Garmin and they sent me a replacement unit.  The second one, a 310 is still going strong, and it hasn't been 100% perfect, but I don't believe any bit of tech is.  I like the Forerunners because they can track runs as well as rides, the 310 is meant to be useable in the pool if you are mad enough to do triathlons, although I have never tried it in the water.

The reason I wanted a new unit was the navigation.  The Forerunners I had only had breadcrumb nav, and so long as you stayed on the right track it was ok, but if you went off course, apart from the message that said off course, nav was impossible. There's no map, just a line where your course is, so if you stray off that, there are no other landmarks shown on the screen to help you get back on track. Running was better than riding, as the pace of running meant the screen better matched where you were; on a bike on a fast downhill it was easy to miss a turn a mile back and the thought of turning round, going back up the hill to search where you should have turned was a deal breaker.

I then saw that Ribble Cycles were selling the Giant Neostrack for £109, 65% of normal retail price.  I have a Giant bike, so read up more.  It has the features of a Garmin 520/Wahoo Elemnt, but significantly cheaper than those two units, so I bought one. 

Negatives - wahoo products you set up using an app on your phone, but the Giant requires you to use buttons on the unit, which is very time consuming and a bit frustrating, but normally you only enter your personal details and your bike details once.  The website and app are very basic, although actual route planning on the website seems a little better than Strava or Garmin - it's a bit less likely to plot a point 50 meters off the road, which can cause confusion on a ride until you realise you don't have to slavishly follow every instruction it tells you.  But once you have plotted a route and sent it to the unit, I can't seem to find it on the site, don't know where it goes, but it would be nice to be able to send the files to mates, or even just a screenshot so they can see roughly where we are going.

Positives - price, I don't know of a comparable unit within £100 of these.  Battery life is a claimed 33 + hours; when I next charge it I will try and check this out.  My Garmins were meant to be 16 hours or so, but unless you keep track of when you last charged it, it was easy to set out on a 4 hour ride with a lot less than 4 hours run time left.  

I have found the navigation ok.  It isn't like a car sat nav, but it does indicate a distance to the next junction with a turn arrow too.  It also indicates distance to plotted points, which confused me the first time as I stopped at one of these looking for a turning, but it was just somewhere I clicked the cursor when doing the route (!)

The Giant blurb says it has a focus on training, I can see there are pre-programmed workouts in one of the menus, and I have programmed a simple interval routine of my own.  I have yet to try out any on the road though.

I'm pleased with it after a month's use, hopefully it will continue to grow on me.

i have a Bryton 450. Navigation is nothing fancy  but it overlays your route/gpx on a map and the battery lasts  ages (30 odd hours claimed but i've never tested for that long). Also can be had for quite a bit cheaper than other computers with map display.

tLike you, I’m shocked by Garmin’s indifference to customer feedback. I’m still using an Edge Touring Plus, for turn by turn navigation, and a big iPhone when I want to look at maps or reliably record a route. (MotionX will record your route and speed all day as long as you turn the display off.)  I’m waiting to see what the next generation* Explova from Acer is like, but also very interested in the Sigma Rox 12.0.  Thanks for alerting me to the Wahoo Roam.  

* The guys at the London  Bike Show said expect something in the autumn.  

I'm happy with my Mio 505. I believe the latest and greatest is now the 605.
They're normally significantly cheaper than the equivalent Garmin and seem to just work.
My only concern is battery life on longer rides once paired with sensors and running navigation. Thus I normally pack a power bank in a top-tube bag.

As no-one else has replied - I use the Elemnt Bolt and am very happy with it. Battery life is excellent (longer than I can ride for anyway) - the longest I've used it for was on a 7 hour hike and it had no problems.

I'm not sure how easy it is to use it for navigation though. You can download routes onto it and it has loads of storage for maps (e.g. all of the UK) but the screen is small and a bit fiddly if you want to be zooming in and out of maps. If you download a route onto it, then you can set it to beep at you when it thinks that you've gone the wrong way which may be useful but I found it annoying the only time I used it (easy to disable the beeps though).