I can tell you that I've plugged my tires about 5 times with the Blackjack kit and never had an issue. This is with multiple track days at Road America doing about 140mph on the straights (not in a V, different car).

Anyone who discredits the premium DIY plug kits just wants you to pay them for a repair or a new tire. Worst that happens with a plug coming out (and again, I've never had it happen) is you slowly get a flat. Big f'ing deal.