I am the Same way.
I started with a Cart n' Atty, an RN4081. But Atty's back in late 2009 were Finicky. And all the Hoops to re-stuff them with Fluval or Pyramid Tea Bags or SS Steel Wool was a Test of Patience. Not to mention Carts that held 7 or so Drops of e-liquids.
Cartos didn't give quite as Good of a hit as a Well Hitting Atty, but they were Dependable. And gave me the Confidence that I could Depend on my e-Cigarette when I left the House. Something that was one of the Last Pieces of the Puzzle to Quitting Smoking for me.
I still have some old cartos around in a box. I started with a Joye 510 and then the eGo. Carto vaping was a natural progression once I bought a Provari. It was a pretty good vape until I began to explore tanks. The ability to fill a tank and go half a day was enticing.