Just finished my first build with a PolarStar F2, the new PolarStar Thing Hop up and the PolarStar Direct Attachment that allows the hop unit to thread into the engine making for a monolithic setup that ensures nozzle alignment.  Used a Maple Leaf 455mm 6.02 barrel, a silicone Macaron 60degree bucking and Omega nub.

Once I got my F2 dialed in and tuned, it's running at about 95psi and getting me 1.95j (a little less than the 2j dmr limit at our field).

Initial impressions are HOLY SH**T!!!  It's one of the quietest, longest shooting and most accurate HPA setups I've put together.  the range is STUPID FAR with .4g.  Some other players with 2j AEG DMR's running .36g that I built for them were coming nowhere close to me ranging them with this setup.  Even as the day proceeded and it started to settle or break in, it just kept improving, and that was probably only after about 200 shots.

I'm breaking it down again for painting, and will take some picks of the Krytac gearbox I put it in and the mods needed to make it work.