While I agree with most, that it would be nice if they were a snug fit in the bottom of the mold, I think it's probably best that they are the way they are. The base is slightly curved upward. This actually allows air to escape early in the process so you are less likely to have trapped bubbles in the candle. This does mean you have to shave wax off the bottom before you pop the pin out. As for the ridge, it's up to you to keep it. If centered, the ridge will be even. If you don't want it, you could shave it off, or rub the candle on a hot plate.
As for centering, and keeping it centered, I put a neodymium magnet under the mold and the pin didn't budge. It also allowed me to stick the cups to an old baking sheet covered in parchment paper. This made for tremendous stability during the pour, and a pin that stays where you put it.
So, all in all, I do like these pins. The only reason I give it 4 stars is I had to straighten all 10 pins. (they were bent to the side) I worry that any given pin might pop out while trying to straighten it. Otherwise, I'm happy with them.

I really like these votive wick pins don't have to deal with the wick while the wax is drying and trying to keep the wick centered. I can make a lot of votives now for my candle business.

I ordered some of these votive pins and this allows me to make votives a lot faster than having to wick them prior to pouring. It wasn't until after my first batch I realized some of the pins were crooked. I straightened them out by hand and now they are fine. There is a gap between the perimeter of the wick pin and the votive mold which leaves a ridge of wax around the base of the candle as mentioned in a previous review by Stephanie W. I use a sharp paring knife to shave off the the wax ridge. I don't typically make large batches of votives but can see where this would be an issue if I did. I do love these wick pins and will be ordering more of them.

Love them, works great! Just FYI, make sure the wick pins are straight, a few were "crooked" when I got mine. Just the look of your votives will be affected

I love the wick pins and would never make another votive without them, but there is a trick I learned to make removal easier. Remove the pins while the wax is still warm - a slight tap on a hard surface and the pin comes right out. If I wait until the candle is completely cool, it takes much more effort to get the wick pin out.