I've tried both. For me, the main problem with the Acros is how deep the heel is. 11.5 (US) Acro felt ok (loose even) if I really try and jam my heel back, but the second I climb in it it gets painfully tight due to the heel angle.
The Gomi's have a much more reasonable heel cup (closer to 90 degrees). 11s felt pretty good, maybe even a little loose (my toes go to the end but aren't scrunched at all). I bought a pair of 10.5s to try on as well, but those haven't arrived yet.
Basically, for me, the same sized Acro felt MUCH tighter than the Gomi, due to the Acro's deep heel cup. The actual sole length is probably more or less the same between the two (Butora's website claims this at least), so if you jam your heel all the way back in the Acro and it's still really tight, I would size up the Gomi's a bit. However, if the tightness is due to how sharp the heel angle is (does that make sense? Like for the Acro, the heel is like a sideways V, but for Gomi it's an L), I think same size should be fine.