@Bloodwing
I don’t like bio’s in general because they tend to leave residue on everything. Just loading airsoft surgeon .3 bios from a speedloader left a white mark on the little ‘ramp’. GBBR’s need reasonably hard BB’s because they are loaded into the chamber with considerably more force than an aeg, which is just fed through an L shaped hop chamber. While I have never used them, if I had to use Bio’s I would go with Geoff’s bio BB’s. I consider Geoff’s to be the best BB’s money can buy currently.
Stock performance out of the box will exceed a TM recoil, so you’ve no issues with performance. The max they can hop in standard form (because of the hollow nub) is .28-.30. For 90% of people that’s more than sufficient. At 20m using .28, my standard gun was hitting a 2” target virtually every time.
In terms of reliability.. I have 3 and haven’t managed to break a single one so far. Nozzle return springs are supposed to break on occasion, but it’s never happened to me, and they’re only a couple quid to replace.
Play style is the major change with GBBR’s. For the first game or 2 you may struggle, but it will improve your game dramatically. I always tell people the same thing. If you see someone at a distance, take A couple of shots. If you can’t hit them in 3, there’s no point firing another. Move closer and reengage. Once you’re familiar with the range and accuracy of the gun and you’ve got an optic set up for that range, you’ll know by eye without firing if you can hit them or not.
Any other questions, don’t hesitate to ask.