Ooh fun matchup. The question is which has the lesser durability. Uroc has that painfully written low showing of being partially frozen and then shattered by a bullet. But even if I ignore that, and I do, I don't see Uroc's durabilty being even close to the uru hammers that were smithed by the best in the 9 worlds and imbued with some crazy powerful magic. Uroc's a rock troll who found some uru and crudely made his current shape. Then again Dr. Doom's Destroyer armor was not Odin's Destroyer and was easily torn apart by Thor.
I could see Uroc outlasting Doom's armor if Doom lacks sufficient juice to keep the armor moving. But, I thought Doom's armor was operating at an impressive level so I'd go with Doom's creation as long as it has the juice.