I still use an old-style two-zipper soft shoulder bag as a carry-on, and it's rarely very full, so I've never had any trouble bringing it onto an RJ. My laptops go into a backpack that also just barely fits into an RJ overhead, so I almost never have to check bags at the ramp. The carry-on is also flexible enough that even when there's virtually no overhead space left, it can squish in somewhere.