Lowes sells some nice LED trims that put off a good amount of light. The problem is they come with an adapter to screw into a regular light socket. You would probably have to cut some wires or wire a new adapter for them to work properly.
He quoted me 75/can to replace them with regular cheap cans that can take any bulb. That'll run me $750 total for 10. He said they would have to remove the old ballasts(I think thats what he called them) and just install the new lights.
Your statement is confusing as to whether he is removing the cans and replacing them with new cans, or removing the ballasts and reusing the existing cans.
I would replace them with new cans. Under title 24 if they protrude into an insulated space (eg attic) the must be Insulation Contact rated and Air-tite. (That applies to the entire house)
Before you buy the cans, you need to decide what high efficacy light you are going to use, CFL or LED, which are required in the kitchen. If it is CFL,you much chose whether you use a straight pin or GU24 socket base.
Because the Can Manufacturers have not standardized on a base or plug type for LED's you are either committing to using a can and LED module from the same Mfg, or you may have to modify the can. Cut the base or plug out, and wire in the plug that fits your selected LED module.
LED replacement bulbs (or CFL's) with the Edison base do not meet title 24.