I think it's really gear dependant on how you want to solo. I HATED, I mean hated solo'ing when I 1st changed to Prot. I struggled thru every fight in tanking gear, kills took forever, all and all it just sucked. I used full DPS gear and DW'ed after I seen how bad it was (for me at least).
Post KZ gear, I can solo in tanking gear better than my dps set. Granted I dont' have the best dps set (some KZ epics that I was allowed to off spec on, the ones that no one needed: neck, R&J trinket, etc). Once I get full dps T4 or higher I'll try the DW way of solo'ing. Just right now in Prot gear, my parry bubble/dodge/block/etc I take not much damage and can run thru mobs pretty nicely, still slower even with king's defender and mongoose on it, but the lack of eating/bandages make it worth it for me.
So to not answer your question even more than I have not... it's up to you, how you feel comfy, what set of gear is better, and what allows you to get the most amount of mobs with little downtime.
Play around, it gets easier with better gear