Hi,
I built a pair about 4 years ago and love them.
Initially I built a pair of speedsters but recycled the drivers (plus two more) into the TMM version. The bass response/extension is amazing. Also, I'm a esl fan but sold all my Quads off (several pairs) and now just use the speedster TMM. The ribbon driver is nothing like an esl but it's much better than a cone based tweeter.
PS this is all just my opinion of course!
Andrew