"A" cards can be pretty good bargains.
I'm not really big on trimmed cards, or cards that are altered, but like anyone who buys nice looking ungraded cards a few end up with me. A couple of the T206s look really nice even knowing they're trimmed.
One thing to keep in mind is what the grading company will give an A grade for. I'm not familiar with any besides SGC, so this is mostly about them.
They use "A" fairly broadly, meaning that in addition to altered cards, I think any card that is genuine but for a variety of reasons shouldn't get a number grade will get an "A" grade. Considering the perceptions of the average collector that's probably a good idea.
When I sent cards in I always requested not getting an "A". That got me a bit of a bonus in info.
While this card got a grade, it could have gotten an A. It's nice, but is nearly as narrow as some ABs. It's as narrow by about as much as another card in the same batch was short. this one got a 40 (it also has a pretty big paper inclusion which probably brought it down some. ) The other got rejected for "min size" and would have been an "A" even though it's completely factory but undersize.
This one as you can see was rejected for the top and bottom having very rough cuts. Also not trimmed, but it would have also received an "A"
Teds Jennings is an even better example. Somewhere along the line they changed the required specs so that the ABs weren't knocked down for being narrow. (Or simply retrained someone)
Years later the card gets regarded more appropriately.
So if you keep a sharp eye on SGC cards graded "A" you might just find a few cards that are a bit better than the grade.