It all varies in details depending on the exact repro you buy, but I've got multiple clones of ACOGs, ELCANs and LPVOs myself so I'll chime in.
For me, the ACOG is the shout because they're always the lightest and by a decent margin, usually cheapest too when you compare decent quality airsoft copies. Smaller FOV compared to the ELCANs because they're just physically smaller, shorter eye relief, but enough to still work with airsoft eye pro and for me the weight saving is worth all that.
ELCANs are in the middle; bit heavier, bit more pricey, but wider FOV and clearer (my ones anyway). Nice when you're static but a noticeable heft added to the gun especially by the end of a day.
LPVOs start getting big and vary in weight but can be rather heavy indeed and even the aliexpress ones can cost hundreds (though they are very nice to look through). I think they look super cool on a lot of builds and obviously you have that variable magnification which can be great, but as mentioned there's also a good chance you'll barely use that.
All of the above can be combined with a piggyback or canted red dot ofc, also looks very cool, but that's more money and weight yet again. Personally if I'm close enough I'm using the magical white bbs as tracers and instinctive shooting anyway.
So yeah, myself, I have a fair few Evolution Gear ACOGs e.g.
https://www.specprecision.com/rifle...wo-VAQk62BRsD4Q4EQbySYRCTcUTeZkuBB8bOImAYqtaA