Yeah this alternate design does the job, but you need to do more to piece this bimba air cylinder design concept together. My guess its gonna cost you more and its not food safe like the rv water pump.
The guy commented that the check valves got clogged with hop particles. This could happen on both types of you didn't take the time to make sure it had settled out.
For about forty bucks I'd stay with the rv pump. It also looks much nicer with the chrome. The other design is not what its put on top of my bar. You'd need to build small wood box around it to hide the cylinder.