Opinions on heads please?

Time to break it down:

360 block (zero decked, +.030)
Stock Crank and rods
KB107 +.030 Pistons
XE274H-10 230/236 dur.
.488/.491 lift w/ 1.6 roller rockers
RPM heads
RPM Air Gap intake
750cfm Holley
Internally balanced

Desktop Dyno puts this engine at:
10.6:1 compression and
392 hp @ 5500
407 ft/lbs @ 4500 without porting

( i used the flow specs from another thread on the board for stock RPM heads)

What do you all think? Pretty accurate? Under-rated or over-rated? I've seen similar builds on this board but no dyno ratings or 1/4 ETs for them?