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[jubal81]

What caps were they Jason?  Kemet film caps are usually pretty decent?  Cant say that for their electros though.

The grey Arcotronics. Had bags of three different values and about half were more than 10% out of spec.

You may want to avoid Y5V ceramic caps then.  -20/+80% tolerance.

I get everything in COG if I can. If not, is X7R.

I'm a Mouser devotee myself, but one one of these discount days I tossed a few bags of common-value caps on top of my order.

[jkokura]

Just because a cap is out of spec doesn't mean you should toss it. I would put it in a baggy and mark it's actual value. Who knows when you need a 1.5nF cap, and you don't have one, but that 1.8nF marked cap registers as a 1.6, which is closer than anything else you have...

Jacob

[pickdropper]

What caps were they Jason?  Kemet film caps are usually pretty decent?  Cant say that for their electros though.

The grey Arcotronics. Had bags of three different values and about half were more than 10% out of spec.

You may want to avoid Y5V ceramic caps then.  -20/+80% tolerance.

I get everything in COG if I can. If not, is X7R.

I'm a Mouser devotee myself, but one one of these discount days I tossed a few bags of common-value caps on top of my order.

C0G (or NP0) are clearly the creme of the crop for ceramics, but man do they get pricey (or impossible to find) in larger values.  As you said, X7R are still pretty good.  I've prefer those, but I've used X5R in a pinch on the more dense MLCC caps.  Their temperature rating is slightly lower, but IIRC, they are similar to X7R when operating closer to their rated voltage.

Cheap ceramic caps are pretty lousy and wander off spec for all sorts of reasons.  The maddening thing is that the capacitance you measure on your meter may not actually be what capacitance you get in the circuit.  They also drift over time (although that happens with X7R/X5R as well to a lesser extent).  C0G/NP0 are generally solid.

I did find it interesting that you can restore ceramic caps that have drifted.  You just need a good oven. :-)