Upload & Sell: Off
I wasn't all that impressed with the C-XPROB when i played with one. The horizontal-vertical switchable centre column is clever and all, but clamp/boss didn't feel all that sturdy to me. I chose to spend a few extra pennies and buy a Feisol instead.
I'm also invested in the Manfrotto RC2 system (486 RC2 ball head), but i kind of wish i wasn't. The Manfrotto heads are ok, but they aren't great and upgrading to a better head means ditching the RC2 plates completely and moving to the more generic Arca type clamps. I wish now i'd skipped the manfrotto system and gone straight to a head with an Arca type clamp.
All that said, i'm assuming you are looking at the discount bundle at Wex and for the price it does look like pretty good value to me.