Belt question for Shield Block set

So, I been working on a shield block set for the leveling grind, and am faced with the following question:

Which belt to use?

Belt of the Guardian - Belt of the Guardian - Item - World of Warcraft

or

Sha Tari Vindicator Waistguard - Sha'tari Vindicator's Waistguard - Item - World of Warcraft

Statswise the guardian is better, but has no block rating. Would gemming it with strength help offset that?

I am leaning towards the shatari one just because of that, am I thinking correctly about this?

Belt of the Guardian with 2x 10str gems.

Yep, I have the Belt of the Guardian with 2 +Str, but the blue belt is very good as well, I just happened to have the mats available to get the epic crafted.