kind of apples and oranges.
I think TSM is VERY overrated. I like it, but I think the hype for it is basically caused by the fact that it's the only family ride you can do at HS. If the kids arent in for the ToT drop, or not 48" for RnR, then the only real "rides" you can do as a family is TSM and Star Tours. This causes the frenzy and the lines for TSM imo.
BTMRR is just plain fun. Funny that pp noted they liked it better in the dark. We liked it in the dark, but agreed that we all liked it better in the light - in the dark it was more like SM.
If I had a choice and could ride either right now it would be Btmrr hands down - it's the best darn ride in the wilderness!