At what point are you rerolling your resto shaman?

[Hachoo]

1) Pick a Shaman that will eventually become Resto.
2) Give all "healing" gear to this character, so you can stockpile it (use outfitter to build gear sets IMO).

When you find that you need more heals, put the "quasi-resto" Shaman in healing gear and try again. If that doesn't work, go respec.

And on this note - this speaks volumes of how awesome the "spellpower buff" will be in 3.0.2. Theoretically now we wont really have to have 2 sets - every shaman will already have more +healing than we have right now because our existing spellpower will also give something like 50% more healing - this will make chain heal x5 GODLY and having 1 shaman on heal duty during a boss fight will be super easy.