Yes, I have installed the kit. It helped with throttle response and idle quality.
Cannot comment about fuel economy. You shouldn't see a MPG loss though.
Took me WAY to long to install because I lost the passenger side fitting by the firewall and could not find it.. After a parts run to town looking for a fitting to no avail, I ended up going back to the shop and looking for it again.. eventually found it under the truck somewhere.