The issue of how difficult it is to disassemble a Ruger .22 autoloading pistol surfaces EVERY TIME this pistol is compared to any other.
While the Ruger may appear to be mysterious to take down (actually it's the REASSEMBLY that confuses some persons), once the user understands the mechanics of what they are doing, it can be done INSTANTLY EVERY TIME.
Ruger does not help matters, in that their instructions in the manual are more complicated than they need to be.
That said, both the Buckmark and the Ruger are fine plinking pistols. I personally like the grip angle of the Buckmark better than a Mark II, but about the same as a .22/45.
The Ruger is harder to learn to disassemble. On the other hand, you need tools to take a Buckmark apart, and you better not loose the lockwashers under the screws, lest your pistol diassemble itself while firing.
I will give the Ruger extra points for robustness. I cannot prove this, but I somehow think a Ruger will be running after a Buckmark is plain worn out. Maybe someone with MANY (50,000+) rounds thru a Buckmark can refute my thinking here..........