I don't know if they make this model anymore, but I use a Telex "Airman ANR". It weighs 6.3 ounces, the headband and earpieces are VERY comfortable (as tested by many 4-5 hour legs in Weswinds), and with the noise-cancelling turned off it offers enough passive noise reduction (more than the 750) while still allowing easy non-intercom conversation. The open-ear design is also "structured-hair-boy-friendly", for you freaks of nature who aren't thinning-out and receding like me.
I know opinions vary, but I find the cockpit of the CL-60 and -65 to be quiet (unless of course your RAT has deployed, but then noise is the least of your worries), much quieter than the hurricanelike noise level in the weird-nosed Westwind flying in the teens at 365Kts indicated . Only then did I ever turn on the active noise-cancelling, finding the passive reduction to be more than adequate for <250kts and upper flight levels.
Unless absolutely needed (and I never have in the CRJ) I don't like the ghostly-quietness of active-cancelling, especially during take-off and climbout. Since you can hear the engines in our smaller aircraft, I'd rather keep my ears in the sensing loop during that critical phase on the chance they might be the first thing to pick up an uncommanded change in engine noise (and therefore, it allows time to plug your nose before the smell of bird-struck, puree'-ed duck guts makes its way forward through the enviro system). In fact, after my first T/O with ANR turned on and climbing through 10K, I queried my F/O if we were indeed really airborne, or had we in fact entered into a Twighlight Zonelike silent movie (at which point he thoughtfully reassured me the world still had sounds by stating "I have the airplane"). Not being in a glider, it was just too surreal for me.
I would decide based primarily on comfort, comfort, comfort... then passive NR capability, followed by Active. Any passive NR will be better than the 750 you've been wearing. The CRJ is a relatively short-range aircraft, and if you aren't planning on flying them forever consider that you might have to whatever you buy for hours-on-end. Don't get me wrong....active-cancelling is a GREAT feature and quiets the din in one phase of flight (lower alts >250kts), which enhances safety, but to me it's overkill the rest of the time so ultra high-end ($) ANR performance isn't worth it. Remember they are trying to sell you their most expensive headset, but nobody ever went deaf from cockpit noise in a jet, and the biggest reason for hating your headset is physical discomfort. As far as hearing loss, it's FAR more important to wear those 50-cent earplugs on the ramp.
Just my $.02
