Schwable Pro Ones vs Conti GP5000's tubeless

My summer wheels (Hunt 44/54's) have always been set up tubeless running Pro One TLE's and I've never managed to get them to seal any better than losing approx 5 psi a day.  Which is fine for a day ride but lousy for a multiday.

In an effort to get them to seal better I replaced the Hunt tape (suspicions confirmed by finding sealant in the spoke sockets) but didnt manage a great seal with the Schwalbes.   (BTW dont buy Peaty's tape - its crap)

Last straw was yesterday on the bed in ride when the front lost all pressure after 8 miles.

Trying to diagnose it at home I managed to get a really good seal, but only for the tyre to split where the carcass meets the rim.   So new tyre time.

Suspecting the Pro Ones were part of the problem I grabbed a GP5000 from Wiggle.

Just fitted it and got a loverly "double ping" from it with no sealant.   Plus point was also that it took a single tyre lever rather than a double knuckle scratching effort with the Schwalbes.  Still to test long term air holding ability but initial fitting is night and day with the GP5000 compared to the schwalbe.

So long story short - Are Schwables just crap quality?  This isnt the first time I've had problems.  I had other pro ones with bulgy tread and Marathons that were lever snappers.  My G-ones were quite leaky too.  Replaced those with wider WTB resolutes which seem to hold air much better.

So in short are Schwable pants or is it just me?