The quality of beer from one gallon brewing equipment versus more robust equipment I'm becoming more interested in brewing my own beer and due to space considerations am thinking a 1-gallon size may be my ideal choice of setup.

The question is:

In what ways does brewing with 1 gallon equipment effect the quality of beer that's produced, as opposed to brewing from more robust and expensive setups?

edit: May have used the 'kit' terminology in a way I didn't intend. Basically what I'm asking is if 1 gallon equipment will produce a lesser quality beer than a more expensive, and bigger setup.
I think it depends on a lot of factors, but you should be able to make high quality beer. You just have to pay a lot of attention to detail. Measuring ingredients becomes super important. A little error can screw up a beer. In bigger batches there is more room for error. Same with mashing. You need to have a really good way to keep the mash at the proper temperature, which can be hard in a small container. Otherwise, there is no reason a 1 gallon batch can't be just as good.