I know this is an old thread, but I just bought a tube of the alpha gel yesterday and gave it a try because my headslick finally ran out, and I must say, I was really quite impressed with the results. I had about 3-4 days growth because I hadn't had time to get into my local shaver shop, and I found that the my headblade never clogged up, it would rinse clean almost instantly whereas with headslick it would normally take a good blasting up close on the shower head.
I also found it gave me a really nice close shave, and it felt a lot slicker (maybe I wasn't using enough headslick in the past?) Only downside I found so far is that I had to reapply to make touch ups, which I rarely seemed to need to do with the headslick, and for apparently being unfragranced it does have that menthol smell, which I didn't mind... but it really wasn't what I was expecting.
On my face is where I found the most joy, I didn't even get a hint of irritation, and because I face shave at the sink to avoid any beard-cidents I could see exactly what was up

I'd rate this very highly as a good alternative to headslick, and as was said previously it is cheaper too, although you do get an extra 3 ounces of headslick, so on a dollar-per-ounce comparison the headslick was actually cheaper.
After first impressions it will certainly be a tough decision next time I need to purchase a new cream/gel