The Art of Strength Bulldog Kettlebell
Towards the end of this last tour, Art of Strength had a pretty good sale on their reloadable kettlebell that came with 50 pounds of free steel shot. I decided to give it a try as it would be much more versatile than trying to lug around a bunch of kettlebells every time they decided to move us, which was often.

I chose the clear coat as it seemed a bit more tactical and lets face it, orange and yellow seem lame. And there is a pink one for the broads. It turned out having a good rugged look. Construction is very well constructed. Size is approximately the same as a 1 pood(24kg). The handle is a bit more square on the top, but the finish overall was smoother than most I've used. Handle was also slightly thicker than a 24kg kettlebell. There's a hex screw just below the handle on the outside as you can see on the picture above. It can be loaded with nearly 50 pounds of steel shot. You can also load it with sand or anything else you can fit in there to use as a load.
Using it was like any standard kettlebell minus one big ceaveat, the hex screw. When doing cleans or any other exercise were the kettlebell flips over on the wrist, keep the screw to the outside. It takes about 3 times of hitting your wrist with the screw until you learn better. After that no problems. The steel shot gives a different feel as it moves inside. Also as noted by Anthony Diluglio it also gives good feedback on form. Keeping the shot at the farthest point during a ballistic move indicates proper acceleration. Fluid movement inside is good, sloppy shot falling means you need to work on your power.
Overall I was pleased with the Bulldog kettlebell. Although I still prefer to have individual kettlebells if available. If you're on deployment or don't have the funds to buy multiple kettlebells this may be a good option.....
But just released is a reloadable kettlebell called the U-Fill It, that is lighter and right now on sale at less than 1/4th the price of Bulldog. This is a big recession buster if your short on funds. I'll let the video explain all about it and show how durable they are. I'm definately gonna be picking some of these up while they on sale. The sale prices end the 17th and are limited to 4 per customer. Go to the AOS store now and check out both these great products!
Edit to add: I forgot to mention the other benefit of a reloadable kettlebell, Micro-loading. Can't move up to the next size bell? With this you could add a quarter pound(or more) a week and make constant progress.