are those AOD drain plug kits any good?

Are the drain plug kits any good? Yes and no. They make draining the fluid much easier, and getting the fluid out before a fluid and filter change, as a sole method for changing fluid, no, they use a nut inside the pan to hold the plug in so when yuo drain it, there is about a 1/2 inch of fluid and debris that stays in the bottom of the pan. I would replace the pan. 1st, its a hell of a lot more sturdy. I have a Performance Automatic aluminum pan and its solid as can be. Also being made out of aluminum, it helps to disipate heat and the extra fluid is a plus. Additionally, on an aftermarket pan, the drain plug is cast into the pan so when you pull the plug, there is no ledge on the inside of the pan. So, If you want only the plug, you can get one at your local parts store for about 3.00, or you can order the B&M kit for 7.00 from Jegs. If you are looking for a complete pan, I would go with PA or Trickflow.
 
If you're concerned about that little bit that remains in the pain when you have a drain plug, you could always have someone weld one in for you. Hell, an exhaust shop would probably weld in the bolt, and grind it all the way down for you for $10.