If you want to compare your knowledge to a guy that's been painting cars longer then you've been alive, then we can have this conversation if you want.
Yes, price matters. If you dont think so, feel free to google search "cheap clear coats" and see the results. If its all the same, why not use the 5$ can from walmart wes?
edit: PPG is a highly regarded paint. If you're skimping on the last stage, expecting great results, you're probably bound for failure. This isn't me being a brat, its pretty much a universal constant. I did my research and took the sage advice from an old master mechanic who's painted more entire cars then you or I will ever paint guitar wise. These aren't my words, they are his. I don't normally hold gospel to one persons critique so I did my research. Turns out when you use cheap paints, they have their own sets of problems. Either they don't dry properly (which is what KEA is having issues with turns out), they yellow fast, or they simply dont hold up for very long. I would figure someone with your experience would be able to understand this.
Also, if everything is the same, why use zpoxy or west systems? Why not get the tube of quick set epoxy from walmart? Should be the same thing right?