That story makes me ask the question; what do you get with a G3 Hemi that you can't with an LA?
Here's what I could think of:
Cross-bolted main caps
Raised cam and better (not perfect?) pushrod angles
Direct shot ports due to opposed values rather than inline
Valves move away from cylinder walls instead of towards them
VVT (on '09 later motors only)
Cam position sensor on front of cam instead of all the way at the other end
Crank driven oil pump
Question is, how much do any of those impact a build? I would guess if you don't go over 600 hp, the stiffer block and increased main cap bolts might not make much difference? If the heads flow similar numbers, will it matter that the LA shrouds the valves as they open but introduces a swirl to the mixture? Crank driven oil pump removes twist from the cam, but how much does that play into things?
Questions I can't answer. Does seem to me that the G3 Hemi is more efficient than the LA in regards to MPG and power, but is that only due to tuning, airflow and compression? Don't know.
For me, the fact that someone with some computing power behind them sciences out the 5.7/6.4/6.2 makes me think they are a better all around motor than the LA. If I was shooting for 6-800hp, that (I think) is a no-brainer, but for my mild goals the differences are probably minor enough to not make a big difference.
Just some random thoughts.