"Once in a while you leave for greener pastures but its one or the other.."
Maybe the case for the vanity posters, but for the normal joe like myself, that is primarily interested in gaining information on sportsbetting and sportsbooks, it's not a problem at all.
The discussions at MajorWager lean towards the sports themselves, while the discussions at the Rx lean towards the Sportsbooks.
Since the information I desire is more sportsbook-related, I seem to post slightly more at the Rx, but it's not because I like one more than the other. I monitor them both, chip in when I have something that may be of value, and go about my business.