I think a lot of it depends on your learning style. You cover essentially the same material in PBL and traditional curricula. You just learn them in different ways. A traditional curriculum teaches anatomy, physiology, biochem, histology, etc, etc, as a foundation. Then you move on to pathology in all its forms, and then you put them together for actual cases. In PBL, you start with a case and from that case, learn all the material that is relevant to that case. At the end of 4 years, you've covered the same material. You've just covered it in a different way. The advantage of a traditional curriculum is that it gives you a solid foundation. The disadvantage is that it may fall short in teaching you how to translate that foundation into clinical practice. The advantage of PBL is that it teaches you how to think like a doctor and not just like a student from the very beginning. Depending on your learning style, it may be easier to permanently retain material learned in a didactic setting or it may be easier to remember if you learned it in a PBL setting. That's a very individual thing.
My experience working in a teaching hospital has definitely influenced my personal feelings in favor of PBL. I know how much I've learned from studying issues raised in cases I've been involved with. Right now I'm studying the role of the kidneys in calcium homeostasis. Specifically because I have a case to relate it to, I feel like I have a pretty good chance at retaining this information for the long term. If I'd learned it for a class, I know I would not remember it nearly as well.
I've also seen new grads make mistakes that I think they *might* not have made if they'd had more case-based education in school. One case that comes to mind was a young adult cat whose bloodwork showed severe azotemia and a K+ of 9. The doctor correctly identified that the cat was in renal failure and took appropriate steps to treat the hyperkalemia. However, she didn't recognize that in the absence of an obstruction in the urethra or ureter, or a uroabdomen (none of which he had), renal failure with severe hyperkalamia is probably Serious Badness (i.e. anuric RF, which was the situation here), and the prognosis is poor to grave even with the most aggressive treatment. This meant the client was told that the situation was not nearly as dire as it actually was. So basically, the pieces were identified correctly but the breakdown came in putting them together to see the big clinical picture. I think PBL can help make this sort of situation less likely, although of course every new grad has a steep learning curve to navigate.
The way I see it, most vets do become clinical practitioners and nearly all of these folks start off their careers pretty much immediately with primary case responsibility, even those who pursue internship training. Being a good clinician comes with practice. An exclusively PBL curriculum should, in theory, provide the maximum possible opportunity to practice these critical skills before graduation while also providing, on average, the same competency in the basic sciences.
Most importantly, know yourself. If you know that a classroom environment is where you thrive, then an entirely PBL curriculum may not be best for you. If you're like me and thrive in a clinical-esque setting and lose 50 IQ points when you set foot in a lecture hall, then PBL may be much better for you.
