Basically agreed with Sitting Duck here. There are quite a few variables.
A cheaper longer barrel will be far worse than a shorter, better finished barrel that's for sure. Thing is, your hop, ammo and the bore size come into play (the hop in particular) when looking at range, and that's why I go with a wider bore because I believe it to interfere less with the backspin as the BB travels down the barrel.
More so than with other bits of airsoft gear you do get what you pay for when it comes to buying an aftermarket barrel. Prometheus/Laylax, PDI, EdGI, ORGA are all excellent barrels from my experience and many others, but like Sitting Duck says, you're not necessarily constrained by the length of your barrel at all.
It depends what you want to do, but most lengths and diameters can be made to perform just as well as one another by changing one of the other variables.