Thanks for sharing. I'm also a Diamond, but rarely check luggage on any domestic flight. But on a recent trip, we did need outdoor gear that we had to check on Frontier. In both directions, the experience was surprisingly smooth -- given that I always expect the unexpected with Frontier. That said, I assume that since so much of Frontier's ground operations are outsourced and there's so much variability with luggage handling in general, just about anything could happen when you give Frontier a bag! I find it interesting that Frontier is now offering Diamonds 2 checked bags per person for each person on the itinerary, but with a limit of 40 lbs per bag. That seems like a lot of luggage (it is!), but it's amazing how heavy gear can get. We had one of those lightweight inflatable kayaks, but when we put it on the scale at home it registered above 38 ilbs. I would certainly weigh anything heavy in advance to avoid any counter hassles.