I have the Bersa and I get to shoot a friend's Ruger 22/45 frequently.
The thing to remember is they are two completely different types of guns.
The Bersa is just a small bore self defense style gun. The smaller sights are on the slide (which wiggles a bit), the trigger is good enough but not great, and it prefers high velocity .22LR ammo to function well.
The Ruger 22/45 has bigger sights with more adjustability, plus those sights are on the fixed barrel/receiver. Out of the box, the Ruger trigger is better and of course is tunable to be great. Also, the Ruger is much less ammo picky and will function with most anything I've tried.
For me, the Bersa is a fun little plinker and self defense practice gun. The Ruger on the other hand is much easier for me to shoot accurately and it still fills that plinker role very well.
One way to think about it would be target size while plinking. Let's say you have both guns shooting targets at 15 yards. The Bersa's targets would be 16 ounce water bottles while the Ruger 22/45's targets could be the bottle caps.