I still have the bench grinder I started out with 40+ years ago, a General Tools 6" model belt driven by an old washing machine motor hanging under the bench. General may still be making them, looks like just this one and is in the same condition:
I keep a coarse wheel and a wire brush on it, and it is my go to grinder after all these years, even though it is anything but smooth running. It has seen a lot of use and never has needed any maintenance.
It is surrounded by two other 6" bench grinders, 3 sander grinders, a carbide grinder, all with various other wheels. One is an old school Baldor, another is a nice Wissota. One is an old Dunlap. One is a Taiwan 6x48" sander with a 9" circular wheel as well. One is the little HF 1x30" sander grinder. For a few weeks I had a 12" pedestal grinder, picked up from H-M member dlane. I finally realized I had no use whatever for it (just looked so cool!) and sold it to another H-M member, Ulma Doctor for what I had in it. The one I want, but really don't need, is one of those 8" ones the OP is trying to make a decision on.
And of course, also several die grinders, a tool post grinder, a Dremel clone, a Drill Doctor 750x, various sidewinder grinders, and probably some more I missed. And a bunch of extra wheels. No wonder I can't seem to make room for the surface grinder I really want to get to play with. 8^)
As you might have guessed, I am in agreement with those who think you should keep both, unless of course if you want to send one to me!