That UKPK from Sandbender came today. Takes a good edge, although I can see what other reviewers meant about the lockup.
The spring tension holding it open is detectably less than my Victorinox Tinker. However, there is a finger choil thingy which means it would be very difficult to close it on your hand. The flip side of this is that it is very easy to open one handed.
We'll see how I get on carrying it around for a while. If the tension issue starts to bother me, I may look at buying the Boker. If I do, I'll do a head to head review and then give away the loser on BCUK.
We'll see.