.. so I grabbed it.
You can see a full technical description on Soligor's site, so I won't bother you with that.
Rather I'd talk about my experience with it. The way I got it was as unusual as it usually is. Seems I seldom buy things the regular way. I have a way of finding deals that come linked with help from good friends. This time the deal was in Vienna, so my mate Raed went to pick it up (and payed it), and I had another friend/coworker that picked it up on his way home. I love it when a plan comes together :)
So eventually I got it, and my first impression was: "wow it's big!". I mean, I did read the specs before buying it, but somehow the 108mm (4.25") didn't quite seems as large as they really are. Holding it in my hand and I couldn't get over how huge this thing is :)
The only lens I can fit it on is my 18-250 from Tamron. At it's widest setting (18mm) it feels nice (you don't get the feeling something is changed with the soligor attached). A simple test (probably way to simple) was to shoot the same frame with and without the Soligor. The difference sure seems like the 0.75 they claim, and I couldn't see any difference for exposure (keeping ISO and aperture constant).
I'll keep testing it the next few days, and post some pics in here.
I looked around for a 105mm UV filter to put on it, but those things cost a fortune, so I just have to be careful with it.