Debating 5.7 or 6.1 swap

Yes. Unless you opt to carb and just run the MSD Hemi 6, pretty much any system (MegaSquirt, FAST, Holley, Mopar Performance, etc) will cover both sides.

I agree, if you are going to modify the engine a lot, then go that route, but the amount of money invested is twice as much. If you plan to stay stock or close to it (cam swap), then go factory stuff.