Yes and no. Do not study those profiles. If you start memorizing the Bombardier profiles, it will only confuse you when you have to change over to Mesaba profiles. They are similar, but still different enough. Also, don't study the limitations. Just because Bombardier has an aircraft limitation published doesn't mean that Mesaba's is the same. Some of our limitations are more restrictive than the manufacturer's.

Studying the systems might be OK though. All that FCOM stuff is almost identical to the Mesaba PSM book (Pilot Systems Manual). You'll get the PSM in your second week of ground school (after indoc), although most people never open it. You'll get a Bombardier PRM (Pilot's Reference Manual) to study the systems, which is a much more readable and pilot-friendly book, as well as a POM (Pilot's Operating Manual), which contains all the Mesaba procedures. That stuff will come soon enough for you. If you haven't started training yet, I would just enjoy the time off. I know you're probably excited to start, but if you study the wrong stuff you'll just make it harder on yourself. Keep it simple and only study what Mesaba tells you to.