Whether editorial opinion matters depends on the editor and the magazine. Many "magazine out now, particularly online mags, are tehre only because someone wanted to start a magazine, even though he has zero experience in writing, or editing, or anything else. The same is true of "editors" at such places.
I've read a lot of slush, and I always read the credits list. If I see a top magazine in whatever genre, I'm duly impressed. If I see, or something similar that I've never heard of, I am not impressed. If I check, and find The Nantucket Monthly is just a nothing magazine started by someone who hasn't a clue, and is filled with bad stories with worse editing, then, you'd be better off not mentioning it.
On the other hand, reader comments really don't mean anything, either, unless they come from my readers. Different readers have different tastes, and one mark of a good editor is knowing what his readers will like, even if readers of other magazines hate them.
But on the whole, it doesn't sound like you have a credit that's going to impress an editor, and since any story you submit ultimately has to stand on its own, I wouldn't mention this as a credit.
