Even though I have a high-pressure connection from my onboard propane I use a portable grill with the 1 lb bottles, which I refill. I bought a refill kit ($8 on ebay) and refill the bottles from my home BBQ tank. I just keep three 1 lb bottles with me. If I have to I can refill using one of the 30 lb tanks on my TT, but so far haven't had to. You have to refill with the (20-30 lb) propane tank inverted, so it won't generally work with a built-in tank (unless it has a bottom connection for liquid).
I like this because I sometimes like to cook further away from the RV, such as near the campsite picnic table or whatnot.
Of course we mainly use the RV for camping right now. In another 7 or so years when we plan to be fulltime in an A or fiver we might wanting something a little easier, not to mention cooking on the grill a lot more where having a 1 lb tank go empty in the middle of cooking would get old, fast.
Michael