The best thing about digi stamps for me is that you can print any size you want and as many times as you want. But you are not allowed to redistribute the files. In other words, if you buy a digi stamp, you cannot pass that file on to friends.
I use Copic markers with my digi stamps. However, I find that no matter how long I let the ink dry after printing it still smears with my copics. So, to avoid that, I print and immediately pour clear embossing powder over the image. Tap off excess and heat. The clear embossing powder keeps the ink from running. I've also tried using black embossing powder but the black smears with the markers so clear works best. I also use Gina K Luxury paper because it's thick and works well with Copics.
Anyway, once I've heat embossed the image then I color. Then I cut it out.
Hope that all makes sense.
If you want to try digi stamping Bugaboostamps.com has a freebie that changes every Friday. Have fun!