To me regulator creep is a drawback of having a gauge on the regulated chamber. The Bullshark does not and I don't think that is a significant disadvantage. It forces users to look for changes in POI or velocity instead of focusing on small movements of an inexpensive gauge. I am not accusing anybody of anything, just observing the POI and velocity is what we really care about.
My 25 Avenger leaked when I got it but Air Venturi fixed it and it has not leaked since. But I was out something like $80 to ship it back to them. It is accurate but my best 30 yard challenge score with it is about 185. All my 3 P35s have done significantly better than that. The P35-25s best is 194, the P35-177 has done a 197 and the P35-22 has given me one 200. I'm hoping to better the P35-177 this year. It seems more accurate than a 197 but it is terribly wind sensitive (like other 177s from what I can gather). This year my best target is a 198 with the P35-22. It is at least as accurate as my Caiman X that cost about 3X.