I have T10i back in my ears as final tour run, just popping in to final things from my end.
I think the best way to describe the differences in opinion with this IEM is....
No matter what filter you use you're going to have bass with this IEM, some bass, more bass, lots of bass, this is purely one strong aspect of T10i which isn't going away without EQ. The best way for me to describe this is.. its very much like listening to music accompanied by a powerful sub-woofer, take a teenagers worked up car with a 15" Kicker sub in the boot or trunk, its always in the background pumping away causing a dramatic amount of atmosphere, that sub-bass presence and decay lingering around. In saying that, in the case of T10i that teenager hasn't forgotten about the mid or top end of his car system, he's installed quality speakers and splitters upfront which bring a nice mid-range and to some extend extended treble etc. He hasn't gone just for bass leaving the front end stock standard, he spent an even amount both ways, this is what I see in T10i.
And..where the difference between people's opinions lies here is all in relation to what I said. Some people absolutely adore sub-bass, you have people of all ages running around installing insane subwoofers and amps in their cars trying to outclass SPL levels, going to meets, competitions etc.. They love bass, simple as that and would enjoy nothing more to have that in a portable solution. Then you have other half who wouldn't set foot in a car with LOUD bassy music, it would give them a headache, they absolutely hate it with a passion as doof doof cars pass them in the street.
I guess one could say they're either matured past that stage or it was something they never liked at all. Myself for example, when I was young would always turn up the bass with my stereo. Yes, I was one of those fools you see at the lights shaking people rear view mirrors, more the better I'd say back then, anything for that reaction. Even when I joined Head-Fi my quest was to try and find car sub-woofer bass levels in an IEM, I purchased Hippo VB, portable amps with bass boost and at that time T10i would have been absolutely perfect for my tastes as it will also be for the next bass-heads inline.
As I grew older or expereinced I became more accustomed to finding detail, clarity, listening for technical ability and really that's what the heart of audio for me grew to be. So whilst I can dig the entire concept of T10i, I can see the approach its not really for me after the path I've taken. Going back a few years I would be all over it as its very capable in what it does, though catering to a bunch of audiophiles with acquired taste for flat response isn't a place for T10i, unfortunately.
I'll give a big ups for:
Build (some of the best I've seen)
Fit (they're incredibly easy to fit for me)
Package ( complete value for money and presentation)
My thoughts for RHA:
Possibly introduce an alternative T10i with lowered bass presence, basically T10iR (Reference). This would leave the bass version for those we've spoken about above (because they're out there) and then cater for the audiophille community who prefer a flatter response. The driver inside T10 have lots of potential, consider retuning it slightly introducing a second version with reference tuning and reference class filters. That's what I'd do in a nutshell to please the other half of consumers.