Neither is really better. Just different.
Tru-oil is a brand name from Birchwood-Casey. It's a blend of linseed oil and other un-identified oils. It's a quick commercial wood finish.
Pure tung oil is a natural wood preservative made from the nut of a tung tree. It has been used for centuries to water proof boats in Asia. It does take more rubbing to get the best finish, but it dries into a hard nearly water proof finish. The more coats you rub in the shinier the finish.