The X9’s trigger gives a lightweight and rapid throttle shift, but slippery grips let them down. SRAM were founded on grip shifters 20 years ago and they’ve been refining the idea ever since.
Twisting the inner grip portion to wind the cable and rip the gears back and forth across the cogs is fast and intuitive. With very few working parts and only one protruding bit they’re reliable, crashproof and knee-friendly.
If you tend to roll your grips to get your front wheel up or control attitude when jumping, there is a risk of mis-shifting, but they’re great for XC. The only trouble with the X9 twisters is that the grip is slippery when muddy and the grippier, more gorgeous X.0 is only £8 more expensive.