I own two pairs of the Shure SE215 models. I have the SE215-CL and the SE215-LTD. Do they "need" an amp? No, not really, they do not "need" an amp. But I don't "need" bacon with my eggs either, but they taste better to me with bacon. Just like everything is better with bacon, almost every headphone can be better performing with an amp. I've run multiple amps to my Shure SE headphones, and must state for my own listening pleasures I require an amp. Do you like to listen to music at really low volumes? Do you listen to music with lots of detail and layers? If you answered yes to either question than yes an amp is going to give you the best performance out of your IEMs. The SE215's, both models I own, are startlingly enhanced by a quality amp. I bought a JDS C5 to complement my Shure IEM collection and I doubt I ever plug my 215's into another jack in their lifespan. I listen to musics of all types, and the 215 just has a much more refined and clear sound to them amped. Details are richer, everything is crisper and by the way they don't sound like "$89" dollar headphones amped or unamped. Amp's are kinda like the gift that keeps on giving, but unlike a fruitcake they are useful.
Just my two cents not adjusted for inflation,
Princess Zero
Edited to add: If you're looking for that ibeat sound profile, you will not get what you are looking for in the SE215-Bk or CL. The SE215-LTD (blue) has a better bass response, but even still you won't get that "at the club" bass line sound from the SE215's that you can pull from a ibeats EQed. I had a pair of ibeats I enjoyed using for select types of music but they share very little signature with the 215s.