I've been here many times from Manker Flats (parking area) to the summit and then to the ski lift to catch on the way back down. It's about 11.5 miles roundtrip and is absolutely beautiful! Always check with the ranger for conditions before you go. There is a small stream near the ski hut on the way up that you can pump but other than that there is NO water so bring your own water bladder! I've seen too many people get to the top and have no food or water, and little in the way of equipment or layers; this is a bad idea. Conditions can change rapidly so go prepared.
Pros: beautiful, challenging hiking
Cons: conditions sometimes hazardous at summit