Abus locks are really nice. I have a couple of abus rim cylinders, and they're very fun to pick. Only picked one abus padlock though, which was when a friend of mine lost the key for the one on his shed ages ago. It was surprisingly easy, literally popped open in a few seconds. The keyway didn't give me any trouble at all, and yes, I use slimlines, however everything I've opened with those I also managed to open with the jackknife (which has regular sized picks in it) so I'm certain you'll have it cracked in no time.
As for the one I had such good fortune with, I forgot to take it home with me, and by the time I got around to asking about it again he'd lost it. However, thanks to my awesome memory (well, ok... the search function on lp101 cos I mentioned it on there before
), I can tell you it was a 55/40. I don't know the difference between them, but whatever it is, the keyway is bound to be the same profile so you shouldn't have much bother with it. Like lockpicker said, once you figure out its quirks and get it open the first time, you'll get it very quickly every time after that just like any other lock. Keep it up!