I use the workouts feature on the 910xt daily and it works great. Only thing that I would like to see changed is the limit of steps that can be added to the workout in GC. In GC it limits the workout to 20 steps that I can enter. (The device itself does not seem to have a limit on the # of steps I can create. At least I have not reached it yet.) My workouts (particularly cycling) often include 25-35+ steps and repeats.
I would also like to be able to (go with me on this one) repeat the repeats. Sounds funny I know. For example: in one of my workouts I do a variable gearing set: (40 sec@100rpm mid gear, 20 sec@110rpm easy gear, and 30 sec @ 90rpm hard gear) and I repeat that sequence 3 times. After repeating it 3 times I rest 30 sec. I then repeat the variable gearing set 3 more times through with a rest after the 3rd repetition and I repeat that sequence through one more time.
As it is right now, I have to enter the variable gearing set as a repeat done 3X and add another step as the rest. Then I add another repeat of the VG set and a rest and again one more time.
It would be nice to enter the VG set as a 3X repeat and be able to repeat that set 3X and be able to include the rest at the end of each VG set.