I don't think there is a "best" something, moreover in lockpicks, though some may disagree with me on that
Regarding pick guns they are no magic tools and I think it's more rewarding and useful to pick pin tumbler locks by hand.
There is SPP review just a few posts under yours, so you may want to take a look at it if you didn't already viewtopic.php?f=1&t=52280
It is not a bad piece of hardware so if you want to get your hands on it, it's all your choice. AFAIK there aren't any pickguns which rise outstandingly from others. Just don't expect wonders, some of your skill will still be required.