A lot of folks who like .45 like the G30 best. Although the barell is shorter, the different recoil spring setup makes it shoot just as smooth. The same phenomena occurs in .40, the G22 is o.k., the G23 (also single spring) is a little stouter, so you would expect the G27 to really buck, especially with the short grip, but it seems to me and most I've talked to about the same as the G23 because of the dual spring setup.
The G30 is about the size of the G23. The G27 is smaller. The G36 is a little thinner, but not as "small" as the G27.
You may want to check the velocity decrease in .45 versus .40 as you decrease barrel length.
All this aside, all of them work great, go bang every time you pull the trigger, and don't go bang unless you pull the trigger.