We had a highly unusual rainfall in the end of January which prompted me to get a studded tire appropriate to use on my geared 26 with a 50mm rim.
At 2.35" the Ice Spiker Pro is really the only option to fit on the wide rim in a standard frame, and it doesn’t disappoint. The grip is great, like really awesome great. I nearly fell three times today, every time when stepping off the unicycle. The grip really is amazing.
I had the tire running relatively soft at 18 PSI. If I were on smoother terrain I would probably bump it up to 25 and see how that feels but at the low pressure it behaved itself quite well with only minor tire suck on sloping dry pavement and really smoothed out the constant 1" transitions between packed snow/ice and pavement on the driven tracks.
The tire is very pricey, as in you could buy a 24" club unicycle for less but it truly is the Cat’s Meow, the Bee’s Knees, and all that jazz.
How’s the Pro different from the plain Ice Spiker?
The old ice spiker was a bit narrower, and they only make the pro versions now. Other than that I do not know.
The tire did surprise me how good it really was. When I mentioned the side pull it was really only when I was geared up that I noticed.
To me it looks just a smidge narrow for a 50mm rim, but it’s the biggest factory studded tire that would fit. Putting it on a 47mm rim would be approaching perfection 
One possible downside is it is fairly loud, I might get some sort of wrist mounted mirror to check behind me every once in awhile when riding in the tire ruts on the street.
Thought I’d bump this for the winter season. I have one of these on my 29er and it is still performing flawlessly on year three. Traction on ice is equal or better than tracton on dirt. They’re great on ice, but they don’t help much with deeper snow; you need bigger tires for that.
Chain Reaction Cycles has these on sale for $75, over 40% off!
Sam