Ele crit build: 20, 22 or 24?

[Gabshooter]

So I currently have a 24 warlock (Destro) running crit build with 28.3% crit chance. However, I'm aware if you play lower levels as 20-23, your crit rating will scale more and you'll benefit more off it, at the cost of not being able to earn gear from higher levels. I know balance has better results as 20, survival hunters have better results at 22, etc.

So I was thinking about now making an ele running the same concept, horde side however (larger variety of crit based items available for shamans).
So I've been debating what's better, 20 or 24. My dilema is constructed as:
20 - No special items, pretty much same set as a 19 twink would run. Running also cloth heirloom helm / legs for haste and better scaling, no Frost Shock tho.
22 - Unlocks Shield of Uncurbed Appetite - Item - World of Warcraft and Frost Shock. Gets slightly worse scaled but still better than 24.
24 - Unlocks stuff as Shield of Uncurbed Appetite - Item - World of Warcraft / Belt of the High Shaman - Item - World of Warcraft / Acidic Walkers - Item - World of Warcraft (can't take quest ones with 8 crit since you're taking belt) / etc. + unlocks Frost Shock

I really don't know how differently will the crit and haste scale so I'm left wondering here, also playing without Frost Shock might be a disadvantage.

 

[Yndigo]

crit is the best build for elementals. Check out the signature for my shaman.

 

[Phrontistery]

Go Haste or Go home.

 

[Gabshooter]

crit is the best build for elementals. Check out the signature for my shaman.

That BiS doe

 

[Yndigo]

That BiS doe

BiS4dayz

 

[Trollguden]

Crit gear with spellpower enchants works really well for me. I'm sitting on 31% crit and like 240 sp if I remember correctly and then I don't have bis shoulder enchant or them awesome gloves.

oh and yes... I'm 24. Elsafrozenxo @ Draenor

 

[Honey Badger]

If your just looking at gear and not abilities. 20 way to go. You lose out on frost shock at 22 and water walk at 24 which helps your team in AB.

Purely stat wise 20 due to scaling abilities and utilities 24. All up to your playstyle.