Originally Posted by
econ21
Agreed. If you have not got a lot of alts, get the heirlooms first. They are expensive, but make a massive difference in terms of your power while levelling. (During the cata tank shortage, I bought every PvE heirloom in the game and don't regret it - unlike JP or honour gear, they don't degrade with tiers. I wasn't even thinking in terms of alts, just did not want to waste the JPs - but they were a great resource when I became an altoholic and levelled 5 alts at the tail end of Cata).
After that, deck yourself out in a full set of honour gear. Every tier. It takes a while, but again can make a massive difference in terms of your power, this time while doing PvP and makes the experience much more fun. It would also be passable for 5 mans as Ret (and you'd best go Ret, or holy, in PVP sadly).
You might buy a JP item if after grinding 5 mans, you have a slot without 463 but even then there are alternatives (e.g. honour gear - all Ret stats except crit are now tank stats too!).