Magnum vs LA block...differences...preferences

So as im pondering my future engine choices im left wondering if a magnum or LA based block is my best bet.

I seem to gather that the magnum block carry some "negative" ora..vs an LA...but short of being limited to fewer aftermarket head and intake options...i cant pinpoint any other negatives.

So assuming a sub 500 horse engine...

There are intakes and heads avail in the aftermarket that support 500 horse for both... PLUS a roller cam...on the mag...

So why one vs the other? Educate me on the differences please!

Seems a mag with an la timing cover and roller cam is pretty much a super substitute for a non roller LA?

Lets hear it! Thanks in advance!!