Why do they look like they do the same job?
In terms of a filter -- the particulate "screening" is one issue that presumably is easier to deal with than the separation of water and "dropping-out" some of the gunk before they simply end-up in the "filter".
The Racor (now owned and under the banner of Parker) that you are planning on use is a relatively low flow model. You don't have a very large engine and robust pump passing a lot fuel. I'm not sure that makes things easier to properly drop-out the water and gunk vs. using a somewhat larger filter system.
If you use a no-name model, I'd certainly check it a lot more often and see if it's really doing its job. That means not only does the filter look dirty after the season wears on, but does the bowl really collect what you expect. Of course, if you TANK and the fuel in it is clean (is treated right, has no moisture, etc.), the the filter doesn't work very hard. The issue comes up when the filter is asked to defend your engine and allow it to get you home. If things are prefect, then you don't need a filter. Of course, that's not likely with a veteran, boat.
The model you listed is a $100 item.
I'd ask a couple of experienced and reliable marine mechanics up there in Georgetown what they think. They might say, with your little flow, who cares -- or they might say you're crazy putzing with such an relatively inexpensive item. Have you asked your mechanic?