The RNC is a $2000 compressor at a $200 price. (Seriously - not hype!)
The problem with the 3630 (and many others at lower price points) are the audible artifacts that occur in operation.
I haven't used the Joe Meek unit, but if it's like their other products, it imparts it own "sound" to a signal sent to it, so if you're looking for transparency, that unit's not for you. In contrast, the RNC is extremely transparent.
I was skeptical when I first heard about them ($2K sound for $200 - sure - sounds like an infomercial...), but after repeated recommendations about these units from the top guns at rec.audio.pro (got top marks even from Fletcher! the fact that he even sells 'em at Mercenary points to their level of quality), I bought into them. I plugged 'em in, ran a signal thru and I was STUNNED. If you didn't look at the meters, you couldn't tell the thing was even working!!! You'd be hard-pressed to find as good value for your money as those little boxes in the audio industry.
Bruce