First off ill say a pistol is like a watch, yes it can be pretty, shiny and functional however at the end of the day it's just an accessory. Say I'm wrong but I've owned 1000$ pistols and 200$ pistols, buy something of decent quality parts and you will be fine. Your biggest desision is gas or Co2 if you live in canada and your indoor fields have resonable limits buy Co2.
Now green gas vs propane, the same guys who use propane are the same guys that use the shittiest gas and oil in their cars because its cheaper. Why spend the money gas is gas right.... WRONG! Propane contains water, water is bad for metal. Green gas contains oils are good for metals... Still with me?
Your pistols breaks or the internals look like shit and you wonder why it's because your Cheap and lazy. Your pistol functions properly and is nice and shiny your not cheap and you actually give a crap.