Pros
Those are really good opportunities for you to gain more experience on your resume while in school. Depending on who your supervisor is, you will get different projects and experience. It's not just strictly "lab research" like the name suggests.
Also, beyond your job, you will learn a lot from your professor, aka supervisor, too. In my experience, I have worked with multiple professors, and they are all amazing people who understand you're still a student, are very flexible with your schedule, and always push for your success.
Big pros: You get a tuition waiver depending on your job's tier (meaning how much work and how many hours per week you work, which is stated clearly on the website and by your supervisor). There's a stipend paid on top of that.
Cons
I haven't had any cons so far.