I held a G2 in my hands on Saturday and played with it for a few minutes at Olympus Dive Center, in Morehead City, NC. It does allow remix and ccr. You just don't know how to use it.
I did not go fetch my Perdix and compare them side by side. But, I had been diving my Perdix for several straight days, including that morning. The G2 screen looked a bit smaller, to me.
I did not see it in Dive mode, but in the surface mode, I went into the menus. The writing on the screen in that mode seemed smaller than the writing shown on a Perdix screen. But, I normally wear reading glasses and I *could* read the G2 without my glasses, so it's not like it is TOO small.
From the Main menu, I scrolled down and went into the Settings submenu. Once I was in there, I could not find any way to get back to the Main menu. The 3 buttons (in that mode) were for Up, Down, and Select, and there was no menu entry in the Settings menu that represented "go back" or "Main". In short, I did not think it was very intuitive at all.
I did like the 3 buttons. They felt solid and the position at the top should make them much less likely to press by accident than the buttons on my Perdix.
All in all, the size and the screen make it a direct competitor to the Perdix - for recreational divers - in my book. The G2 manual talks about CCR and Trimix support, but the actual unit only allowed for Nitrox (no Trimix).
All in all, the slightly smaller screen, the proprietary algorithm, the non-user replaceable battery, the non-intuitive menu navigation, and the price would have me buying a Shearwater Perdix over the G2 any day of the week. No contest. Even if I already had a SP transmitter, I would just sell the SP transmitter and buy the Perdix AI with a matching transmitter for it. If the G2 were $200 or more cheaper than the Perdix, then I might consider the G2 for someone who had zero tech diving aspirations.
ScubaPro really should have brought the H3 to market, with AI, in my opinion. I dived my H3 and my Perdix AI together all last week and they were both awesome. My H3 continues to be flawless and matches the Perdix within 1 foot and 1 minute of deco at all times.