You could have named this thread "The MS-64 dilemma." C, B, A... in that order for myself. Of course, I'm held to what the market is offering at the given time. For certain year and mintmark varieties, the option to pick and choose is also inherently diminished.
Here's a good example of an "A" coin I recently purchased on ebay and took a small hit on. Listed as GEM by a major washington dealer I wanted to try. Notice the complete lack of chatter in his pics.... I grade as a nice 63.