You still want to go to a good lab. E6 film is even more sensitive than negative film when it comes to slight variations in chemical temperatures, concentrations, or processing times. If you go to a place that keeps tight quality controls on their processing machines, then you'll be more likely to get film that has accurate color and exposure. Also, I've known a couple labs that have a nasty tendency to scratch any film I give them to process, which in itself makes it worth going to a better lab.