What is it you want to use the gas analyzer for? If you are looking to make sure you can pass a smog test, ok I can see this discussion. If you just want to tune for performance/economy, an Innovate LM1 wideband is a lot more cost effective and a lot easier. 5 band and LM1 covers the wide spectrum of whats available, lots of choices in between depending on your needs.
I am not current on Snapon as far as portable gas equipment, but I think you need some sort of equipment to read them, IE Modis. There are better more cost effective units available, I am not up to date on whats out there, but if you are an iATN member, I would search their forums. AES,
http://www.aeswave.com/Gas-Analyzers-c479/ , have some equipment. Jorge is a great guy, and will help you make your choice.