Well, I don't have a PPK available for comparison, but they do see to me to be about the same size. And about the same size and several ounces lighter than a Makarov. As far as the quality of the Bersa is considered, I'm suitably impressed with mine. I bought mine NIB only about 3 weeks ago and I've only got somewhat more than 700 rounds through it now, and that's not a whole lot of time to evaluate the pistol for durability and such, but I've had no major problems with mine so far. I was having some feeding problems, but I think that is a combiniation of not being really broken in well and I don't think I was using enough lube on the metal-to-metal moving surfaces. My fault, can't blame the gun for that, in other words. Bersa Thunder .380's in general have a tendency for the grip screws to work loose every 100 rounds or so (mine does), supposedly a little locktite on the threads clears that up but I haven't gotten around to doing that yet. In general, the weapon seems well made. And they have a reputation for durability, although I haven't had mine long enough to give you a first hand report on that. Accuracy has been remarkable, I'm impressed. Aesthetically, the only negative I have against it is that it has an external trigger linkage, but it seems to work ok and right now that's all I really care about. Both the DA and SA trigger are pretty good, much better than I expected out of an inexpensive pistol. All in all, I think it is one of the best values in a new pistol out there. The general consensus at the range/shop I shoot at is that it would be worth twice the price.
Just like everything else in this world, it isn't perfect, and in the spirit of full disclosure here are the negatives that I have encountered: First, there's that annoying little problem of the grip screws -- not a biggie, but a problem nonetheless. Hey, they had to have give us something to gripe about! The external trigger linkage might be a source of problems down the line or when CCW'ing, it may collect lint, so make sure you keep it clean. Sometimes the automatic slide stop at the end of the magazine doesn't work -- this seems to be crud related and doesn't start happening until 100 or more rounds have been fired since the last cleaning -- again, not a real big problem. It is a minor annoyance at the range and shouldn't be a CCW issue if you keep it clean. The gun only comes with 1 magazine, and be prepared to shell out $30 or more for spare Bersa factory mags. ProMags are the only 3rd party mags that I have heard of, I got 2 of them (just over $15 apiece plus shipping from Midway) -- some people don't like them, but the ones that I have seem to work Ok, but I'll just be using them as range mags, I have 2 factory mags for SD ammo. Another major gripe is the lack of 3rd party support -- not much in the way of specific designed holsters are out there for it -- yet. But it is close enough in dimensions to the PPK and the Makarov that there's enough out there that work well enough. There seem to be no 3rd party grips out there for it at all. None. Hopefully that will change as more of these little gems get into circulation. That said, I really don't mind the factory grips, they work. One last problem that I have encountered that I haven't heard discussed is that after firing 450 rounds through the gun this week, I got a little "bite" from the beavertail tang on the base of my thumb -- not from the hammer or the slide, but from the beavertail itself, there is a slightly rough edge on the safety side of mine. Not a big problem, and may be isolated to just my gun.
All in all, I'm pleased with the one I have. It is well worth the money. In my opinion, this is an inexpensive gun, but not a cheap gun.