I planned to use size M for my daughter when she grows up to about 147cm, but decided that I order second frame, size S for her. She will use S up to 157 and M above 157 or so. I'm 175 and I've got L, but I use 35mm stem and 16 deg sqlab bar that moves hands about 3cm closer to the saddle. With "normal" bar I would have to buy M. S has 445 reach, but with 77.6 saddle angle you will be a lot closer to the bars then on old-school 74 deg STa frame.
I've ridden this frame this season and it's very nice, very capable bike. HTa is bit steeper then on enduro bikes, but this makes steering easier as the "flop" is lower.
If I were you I'd go with M+35mm+sqlab16 to get longest bike possible, but if you prefer 9deg bars then S+35mm stem should be fine.
I wouldn't buy 120mm 909 as it rises BB too much.
Blur TR has HTa 67.1 and STa 75.1, so it doesn't come any close to 909. You will be about 2cm farther to the back. Climbing with steeper STa is so much easier actually.
I'm 5'5" (165cm) tall. Anyone my height or shorter riding this frame in size Small? What length stem you using? Honestly, I'm not about sizing as it has 15mm longer reach than my Enduro bike! And longer reach than most XC or DC bikes I've seen or tried. I understand the steep STA helps and the ETT is fine. But does this bike feel balanced when cornering and do you feel you need to stretch out to properly weight the wheels?
I am consider this frame in 120mm or the Santa Cruz Blur TR (much shorter reach, but slacker STA).