I only have a handful of graded modern cards. A couple that came in packs, a couple that came with other stuff or were less than the grading would be. All three companies, and maybe a couple from some random brand X grader (From the local guys dollar box, and cards I'd have paid a dollar for anyway) and a few I sent in to SGC when they had a special for modern cards at I think $5 each. The ones I sent in I checked the populations with PSA, and all of them were pretty low in high grades. Of course, they didn't do all that well even though I thought they were really in great condition - Nice corners, centered, etc.
There's a few I might break down and send to PSA. I hate the whole concept of paying someone so I can pay them more.........But the difference in price will probably make the difference.
Overall I'm not too picky about grades and who graded it. If I like the card at the price there's a decent chance I'll buy it.
The value also isn't a big thing for me within reason. Having collected a lot of my stuff back when it was nearly worthless - And a big portion of the rest that was not expensive but is now nearly worthless- the price is just a way of keeping track of things. Most of the stuff I really like I'd still keep if it became entirely worthless. 88 Donruss anyone? Ok, pretty close to worthless, and if the good stuff becomes worthless those might be worth more as heating fuel.
Steve B