Hi David,
Yeah, I like the Microspikes a lot. For me, they have the best balance between durability, weight and performance of all the traction devices that I've used.
Good question about the high and low temps. I didn't carry a thermometer, so I don't really know precisely. But I just checked Snotel for the night I was out and their sensor in Wild Basin at 9,560' recorded a low of 25F. I was camped about 700' higher. Normally, I figure the temps drop about 3F for each 1000' of elevation gain, so the low was probably around 23F at Sandbeach Lake. I don't even want to know what the wind chill was. ;-) The Snotel sensor recorded highs of 44F and 46F for the two days I was out.