I have both a Beretta Model 71 and a British L66 (a german military proofed Walther PP in .22 LR).
Comparing the two, both are very well made and very enjoyable to shoot.
The Walther has the edge in accuracy, and with only 8 rounds loaded in the magazine it is very reliable with ammo it likes, and it's a little picky. Oddly enough mine prefers Remington Golden Bullets that no other semi-auto .22LR I've ever owned would feed reliably. The magazine technically holds 10 rounds, but I've never seen one that would reliably function with more than 8 rounds loaded in it. The slide is thinner and lighter than a PP in .32 ACP or .380 ACP, as is the recoil spring, but it's still fairly heavy. Consequently, it generally needs high velocity ammo and 40 grain bullets for reliability.
The Beretta Model 70 and Model 71 use an aluminum alloy frame and accommodates an 9 round magazine - however, I've never had much luck getting the first round to feed reliably so it has essentially the same practical capacity as the PP. In both cases I'll load a 9th round in the magazine and then manually chamber it, leaving 8 in the magazine.
It's not quite as accurate as the fixed barrel PP, however with 8 rounds in the magazine the Beretta has reliability in spades. The open topped slide design is lightweight and inherently reliable, and it's one of the rare .22LR pistols that isn't terribly picky about ammo, eating both standard and high velocity rounds without being too finicky about brand.