Proof doesn't reveal some things
I ordered the printing of my own slant on oval nationality stickers, and chose Make Stickers because they were among the few who would print the size of oval that I was looking for. Uploading my art was super simple. Ordering went well. Got a proof and okay'd it and all was well. I left it at free shipping as I was in no hurry, and it arrived in a very reasonable time.
One thing about the proof is that it can't advise you about your choice of "glossy" or "matt" finish. You are left to take your chances that you'll like what you get, if you're not already familiar with the difference. The matt finish actually makes the black in my stickers look like a 75% greyscale in comparison to the previous batch I ordered elsewhere. This lowered contrast actually give a visual image that the lines are blurry. Wish they could have offered some photo examples of how the finishes differed.
The other thing I'm not excited about was that these are clearly printed onto sheets of perforated oval cuts and then punched out later as opposed to a more clean die-cut process. It isn't as professional as I would have preferred if there were no residual snags of paper on the edges of the stickers.
I think in the future, I'll to a short test printing run, though its way more expensive to just print a few.