Ax15 Trans
My friend when I was in HS had a 4 cyl dakota with one of these. It's not the slickest shifting transmission by any means and the 2-3 shift is a big rpm drop. I think it will hold in a sub 400 hp applicaiton.
I also own an original 3.5L 5-speed 2004 Colorado with the AR5, the upgraded version and it still has a big 2-3 shift RPM drop. You really can't rush a 2-3 or 3-4 shift that hard. Owned the same truck for 15 years and when I got it it had 25k on it and still shifts the same now. I have seen people put them behind turbo LS' but they have broken them with those. The only AR5 with good ratios is the Solstice / Sky one.
I can honestly say its not in the same league as a T56/T56-Magnum for gear splits or shift quality.