Probably on medium, radeon cards are notorious for being terrible with shaders
Nuh uhh
I have a Radeon 6870 1GB, which was a mid-high range card in it's day (It's like 4 years old now) and it can run max shaders fine up to about 10k bricks. High shaders up to about 100k bricks.
I don't know exactly how it stacks up to the card in this build but it's two generations newer so I suspect it won't be too bad. As for the specific question of 'will it run max shaders?', I'd say probably not to a very high brick count.