Experience gear can cut your play time by as much as 20%. But you need to keep upgrading your gear or else the bonus experience won't be enough for your current level. Having a bunch of sets of experience gear every few levels will help. Just so you know, you don't really need full sets, just a few pieces to make a difference on your next character.
Also, if you are running out of space and don't want to upgrade your shared stash, the best way to keep them is to create a few extra characters and pass the gear to them using the shared stash.
This will also save you money, but eventually, you should upgrade your shared stash to avoid wasting time moving items between characters.
