Hello, welcome here. I haven't heard either of those sets that you listed (except the Monarch MkIII that is similar to the Prestige), so take what I say with a pinch of salt. When I'm buying sets, I read the FR graphs, because the overall tonal balance is there. So I thought I'd give you a quick run-down of what I see. Hopefully others will chime in.
The IE900 isn't bad at all (healthy amount of bass, though slightly warm; impressive treble performance for a single DD) but has a quite recessed upper mid-range, so you can mostly forget engaging, present vocals, and instruments that have their upper harmonics between 2-5kHz. Some like this coloration though. Be wary of fakes. A good
review.
The Xelento 2nd gen (is this the "remote" version?) has a similar recession but it's "better" done (sounds more like how our ears naturally hear). However, it also has way too much bass and lower mid-range to sound "accurate," that is, fundamentals and lower harmonics will sound louder, whereas the upper ones will be, comparatively speaking, recessed, so if you like a full-bodied, meaty sound, at the expense of realism, it's the way to go. One
review,
another.
In comparison, the Prestige actually has natural lower and upper mid-range, which is, I think, vital to the genres you listed. However, it's not without its faults: the bass looks to be a bit boomy and the treble is spicy. The latter could be helped by choosing medium and narrow-bored eartips -- in theory. However, it's telling that Thieaudio released the Ltd that has more even bass and a more palatable treble. A good
review.
So if you have no other options, it will be a compromise somewhat along the above lines. But let's hope others will disprove what I said.