Steve,
A group of friends and I summited San Jacinto on March 27, 2016. This was my first hike away from San Diego County and my first 10ker. Having done all my hiking in San Diego County I was not even aware of microspikes. I can tell you after that hike I most certainly researched them and bought a pair Kahtoolas.
The snow was as much as 3 feet deep. I know this because I found myself hip deep a couple times when one leg would fall through (be careful if you wander off the trail). Bring a compass or GPS because the snow made following the trail difficult as you neared the summit.
That being said, we summited with no trekking poles or microspikes, however they would have made for a quicker and less difficult hike. It was a glorious view at the top and I wish you well. Happy Trails.
.
