Holley/Demon Carb stumble

That's the first one that you found and i bought.
At this point i might as well by a new metering block from holley.(134-131)
If i knew what i was doing i would buy 2 of these (but i don't)for 110 bucks
HOLLEY ULTRA HP Billet Metering Block, for GAS, fits QFT-BG Carburetors too | eBay
Instead of one of this one ( 134-131) for 80 bucks.
Holley 134-131 METERING BLOCK 90127025529 | eBay