Sure wish I went 9.5:1 vs my current 8.5:1. Look the 2011 5.0 is over 11.1 and can push 6psi... On a roots blower and 91 octane too...
If you can afford the coin for a few dyno sessions and a good tuner, do it. Tho, you'll never be able to use a race blower (sci, ysi, t, novi2k, f1) at its best efficiency (>12psi)..
With 91 octane I will agree with you. However, if the OP uses 100 octane or even better E85 in the future with a face blower it will be just fine with 10.5.1.