Do it!
I bought a little used 09 Litespeed Hummer last April and I'm loving the sublime feel of the ride! I'm 5'10" and the 17" frame with a 90mm stem and low rise monkeylites suit me perfectly - but we all seem to like set up in our own ways.
To put into some perspective,I bought my first mtb in 1988, and a succession of 2 steel framed hardtails including a paint splatter Explosif (which was fab!)until 2000 when I got my SC Superlight. I also have a P7 that my SO rides now as a daily commute bike. I love my superlight and still ride it but since getting the Hummer, I'm torn as to which one I take out!
It feels strong yet light and nimble (I've put some 100-130 TALAS on it), certainly comfy enough for long days out and whilst I'm not a phat air type, for the kinda XC stuff I do with the occassional launch off steps n drops, it feels like it could do more than I can/want to.
Chain suck is a bit of an issue, but I've yet to fettle with the chainline, so I just give it some mechanical sympathy when dropping into the granny ring and back off a bit on the pedals.
There have been reports of Ti frames cracking and whether thats because of the material or some lard-arse dropping and jumping stuff that the XC label isnt designed for, I dont know. As far as I'm concerned, I always wanted to capture the zing of steel with the sharpness just rounded off a little. I was looking for an XC weight and responsiveness with a measure of longevity. I believe I've found it with the Hummer.
Other people here will always be entitled to their opinions and I daresay, some are based on personal experiences. This is mine. I love my bike/s!