I've had good results with the CAREGY brand from Amazon. I started with this assortment, and have since picked up a few rolls of the colors I use most. Everything I have done, t-shirts, jackets, hoodies, cork beverage coasters, it has all held up well, with no peeling or cracking. The clothing, I machine wash cool and tumble-dry low, and even after a couple dozen washings, they look great. Still no peeling, curling, or cracking.

I don't have a Cricut press or any other heat press, just a dry clothing iron. I lay the decal with its backing on the garment, cover it with a sheet of baking parchment, and press it firmly for 5 or 6 seconds. I then gently hot-peel the backing, making sure everything got transferred, and with the backing removed, I replace the baking parchment and firmly go over the entire decal again, for about 15 seconds. No discoloration, smearing, or curling.

I haven't measured my iron, but the dial goes up to 6, and I run it on 5. (Super scientific, I know.)