I bought an All Star HSM when I started umpiring last year. I wore it a couple times in the fall and didn't mind it too much. I wore it for a scrimmage or two before the season this spring and decided that I just didn't like it all that well. I didn't like not wearing a hat, I didn't like its bulkiness (Even though it wasn't that heavy), and I thought it was a little difficult to take off.
This is all just my personal opinion, as I sold it to a board member here (Hope he likes it) and bought a Wilson titanium for about the same that I sold the HSM for. I used to catch and I always wore a standard mask, so I like the titanium a LOT better. It's unreal how light it is, it's very easy to see out of, it's very easy to take off, and I can wear a hat now.