I am not having any trouble with the fit, I have inserted them all the way so the blue is completely in my ear and just the wire is sticking out. My ears are bleeding quite badly but at least I got them in. I am afraid to take them out.
Okay, just kidding. I am using the tips that were attached to them in the box. I have been using IEMs for years so I know what a good fit sounds like. I have a good fit. Lots of bottom, lots and lots of bottom. Mids, where are the mids? Mids seem pretty recessed. The highs seem fine. I've spent a week with my 535s, and a few hours with the TF10s. So far I'd have to say the 535s are a lot more fun to listen to. A lot more. Not to say the TF10s are bad, I'm just not enjoying the sound as much. But I'm still listening. I think if I had to say what the big difference is between the two I'd say it's "presence". Listening to Elvis Costello (This Years model) Elvis is right up front and prominent with the Shures. With the TF10s he's in the room, a bit away from where I am and I might just ignore him if he stays there. Pop the Shures back on and he's hard to ignore, right in front of me. The Shure 535s are more involving to me. The TF10s are pleasant, but not as interesting.
My wife tried them out and while she feels they are way higher quality than she thinks she needs or can fully appreciate, she will accept them as a Christmas present. Fun.
Unfortunately I bought two pairs of them. Worse things could happen. What does it cost to turn these into customs?
I don't understand why someone would want to swap them and use them backwards for more comfort. I'd be interested to see a picture of how you have put them in before and after the switch. My ear canals are small but I'm having no trouble getting a nice fit.