After decades on SPD's and not really using them for the road I know know the platform SPD's are the way to go. I even use them on my fixed cog that I do 30 mile, 2,000 ft loops with every week. The pedals are easy to step into (really important with fixed cog as you chase the pedal) and a great shoe platform for when you're spinning at 160++ on steep descents. The added bonus is SPD's are great to walk around in unlike my Looks or Speedplays. I used the tiny XTR's for X-Country Racing and Bike Parks but I never did like the lack of shoe support which is vital when you're standing up steep grades at maximum effort. These platform series do it all well.
It is a quality made pedal that gives a solid pedaling platform and good resistanceprotection tofrom rock strikes. I use these for cross country and trail riding. Good for climbing. Easy to get out of when you have to bail out.
Great quality SPD pedal that is too long to hang fast corners on the asphalt, but probably ok in the dirt. I thought the shallower 9120 stack height would help, but it was the length crank to pedal end that hurt. Switched to the short axle version of the 9100 spd.
Great for all types of mountain biking and when you want some support for more flexible shoes. You may want a smaller profile platform if your normal habitat is a rock garden to avoid pedal strikes. Make sure your shoes have adequate clearance around the cleat or it may be hard to get the cleat in.