I prefer the Buckmark due to the ease of cleaning and the modularity, not to mention how inexpensive replacement parts such as extractors, recoil spring assemblies, firing pins, etc. are. Get one of the new models with the enhanced slides (wings at the rear and/or full height slide serrations). They're much easier to operate if you get hammer fall on a dead round.
I am a big 22/45 fan personally. As far as them being difficult to field strip yes they are horrible the first time you do it, and it will probably take a couple times to get it put back together right. After that first heartache it is a snap. I can field strip mine in way less than a minute now, and it is about that fast to get it back together. I like the 22/45 becasue of the grip angle. The buckmarks are nice as well you really can't go wrong with either.
I have a Ruger Mk 2 and a Browning Challenger III, of the two I prefer the Browning. Its easier to clean and clear the occasional jam than the Ruger.
However I think they are both great guns.