I'm wanting to do this for our Christmas turkey this year. Anyone else here tried this or something similar yet?
http://youtu.be/G9eYw2THaeQ
I've used the injection mixture/seasoning in that video previously when frying turkeys and I must say it is pretty tasty. Haven't used it yet on the grill as I have been using the BBQ Pit Boys recipe (http://bbqpitboys.com/recipes/cajun-smoked-turkey-and-pork-roast#.UremePSIz94) for several of the Turkeys I've grilled this fall which have all received rave reviews, but since it is officially winter perhaps I'll try the store-bought version to usher in the new season! The only thing I'll do differently than the video is go breast down for the first hour, as I think it helps prevent drying out the white meat.
I used the same injection in the video on my Thanksgiving bird. I didn't inject the whole jar, but about 75-80% of it. I saved the remainder for basting while smoking. I injected the night before the cook. I put two whole sweet onions in the cavity while cooking, but did not use any rub/dust anywhere. worked awesome. a little more detail on my results can be found in the turkey noob thread
http://weberkettleclub.com/forums/grilling-bbqing/wkc-turkey-noob-thread/30/
I used most of a jar of Cajun Injection butter creole when I did my turkey for Thanksgiving. Then I just did the BBQ Pit Boys method for most everything else. Turned out great. 14lb bird took 4 hours and 20 minutes at right around 300 degrees.
http://bbqpitboys.com/recipes/turkey-with-stuffing-and-wild-turkey-gravy#.UriGTidNk9U