I think the midi controls on the 500 are really done quite well. Although to use it as only a midi controller requires some set up of patches regardless, and there are limitations. I do wish it had a "midi controller" mode. The software makes set up quite easy compared to what I see in the manuals of most dedicated controllers. I like that you can send different types of messages with one button.
My question... Is there an easier / better dedicated midi controller out there at this price point?