Actually I find the T5 gear completely unnecessary so far with what I've been doing. I've successfully soloed Kara and MC completely without it. Prince was a little tough going into that Phase 2, but I used superior damage to push quickly through it instead of relying on the heal.

A lot of hunters forget how positioning is important for the pet tanking, an example in Golemagg in MC. Frostheim had to use two T5, but I found it was prolly because the Turtle tank wasn't positioned correctly to DODGE all hits from all 3 mobs (Golemagg and his two pups), hence receiving far more damage than he should. Since I play a tank on my main, I knew about the positioning requirement and about never having your back turned to a mob. I simply had my turtle stand in such a way that he is always able to dodge any incoming hits. This, plus using Power Auras to keep track of the Magma Splash debuff and spaced out use of pet cooldowns, my pet never went below 60-70% health.

Link to my armory: http://www.wowarmory.com/character-sheet.xml?r=Ner%27zhul&cn=Tirei

I think I only own one piece of T5 (still as yet not bought with the token), and I use 4 pc Relentless and various high stam pvp gear for my extreme solo set, using that BM spec as my solo spec.