Among other genres, I listen to a lot of post-rock, drone, IDM, ambient, minimal techno and other associated genres (
http://www.last.fm/user/scatteredshadow/charts?rangetype=overall&subtype=artists ). I've also just replaced a set of two year old SE-215's that were murdered by an errant foot, with the Yamaha EPH-100's.
To be honest, I haven't found either one to be ideal, although they are both good performers in different respects. Both models are pretty well built, but I'm not sure that I'm confident that the Yamaha's cable can withstand long term daily use. The cable itself is pretty thin, and isn't as robust at stress points. On the other hand, I did have to replace the SE-215 cable after a year. The Yamaha also is more fatiguing, both in terms of the sound it produces and physical comfort. I find that I'm CONSTANTLY fiddling with the Yamaha's position in my ear. Even slight changes in its orientation within the ear canal changes the sound dramatically. The flanged silicone tips slide around quite a bit no matter what size I use.
The Shure's are definitely slower, darker and warmer. In terms of comfort, they are unquestionably better for my ears than the Yamaha. If you use foam tips, there is currently no great solution for the EPH-100, while the SE-215 have compatibility with the pretty much any of Comply's lines and I'd imagine other tip makers as well. That said, I slightly prefer the sound of the Yamaha when they are positioned properly. My favorite over the ear headphones are my Grado 225's, so it'd be accurate to conclude that I prefer a faster, more energetic sound, which the Yamaha produces compared to the Shure. The SE-215 isn't bad by any means, it just isn't necessarily ideal for music that isn't particularly dense or oriented towards vocals.
To conclude, I'm not recommending you get the Yamaha, but perhaps something that sounds more like the EPH-100 than the SE-215, but can be worn over the ear and aren't as hard to fit.