Hi I’ve recently bought a 2014/15 rose Xeon crs 4000 frameset it’s in immaculate condition. It also came with saddle, seat post, stem, handlebars and a set of unbranded carbon clinchers which are also immaculate. All it really needs is a full groupset including callipers. I’m undecided whether I’m gonna keep the bike or sell it on once built. So I guess what I’m after is advice on what groupset to buy. With it being a secondhand bike is it worth spending lots of money on a groupset (Di2) and would I get my money back if I sold it? Or do i save my money and go for something like 105?