Which weep vents for facing brick?

[ruggers]

I need some weeps for my grey facing brick perps to go above the trays.

 

Theres the taller thin cassette type, roughly 10mm x 60mm

 

Or the peep weeps. 

What are most commonly used?

Looking at muck drop off from the builder I'd imagine a much higher chance of a peep weep getting blocked. The grey ones are the exact same colour as the brick.

[nod]

I find that clear work best with most finishes