Eh, no strong opinion. I kinda liked him, but OTOH he's exactly the kind of player that you should be able to upgrade from given a full offseason to do it. And I still have irrational hopefulness and confidence in Roberts based on what he did in just a few preseason games. If Roberts makes it to the regular season without injury this year I think he's an immediate and substantial upgrade over Johnson, and I wouldn't be totally shocked to see him starting.
I'm also betting that Brown will be back, although at this point I'm of the opinion that you can't count on getting more than 4 or so games out of him before his foot betrays him. I think he only makes sense if you have him on the cheap and have built your roster in such a way that near-inevitably losing him is only a minor setback.