I haven't heard the HD202 so no comment there.
I have had the RX700 for over a year and half and it is really a very fun can for most uses. I have much better stuff now like Beyer's DT880/990, Fischer's FA-002 and a couple others, but the HA-RX700 still gets some head-time surprisingly enough. In my experience it is very good for things like classical, soft rock or psychedelic music like Pink Floyd etc. It is a great sound-stage and generally very good sq if your music is properly mastered. It doesn't do very well with pop, or metal (well some metal).
I know the 202s are much smaller and completely closed, while the Rx700 is semi-open (but it leaks like hell!) and it is enormous. If you want to move around with these, then 202 is your only option. If these'll mainly be at home, then you only have to weigh the sound quality and comfort issues. I suspect the RX700s will be more comfy since they have really big pads and a very comfortable head-band system, but the 202 may be decent too.