The exit row of the CRJ70 has much more leg room than any other row on the plane. This is not true of the CRJ50 or CRJ40.
The only way that I feel comfortable in a CRJ is if I have an empty seat next to me. I like CRJs for the fact that they give me more service to smaller markets. On routes that Delta serves with a mix of RJs and mainline equipment, I will go out of my way to take the mainline. I like to upgrade. I have even connected mainline to mainline in ATL to avoid a non-stop CRJ from my home base of CVG.