Philip Bloom Signature Series Pocket Dolly, and have to say I'm very impressed. I bought the 3' model, mounted it to my 504HD fluid head, and went on a slider mission. While being ridiculously lightweight, it is still an extremely well-made piece of alloy metal (7 lbs). I found the sliding action to be very smooth back and forth, and it even works really well as a vertical dolly. I used a Manfrotto 496RC2 ball head mounted to the included flat mount adapter. This gave me a quick way to mount the horizontal slider moves, as well as the vertical stuff.
< In vertical dolly mode
It will also work with the Kessler Elektra drive and Oracle systems, so you can motorize your real time moves and time lapses. The drag control can give you the variable friction you need, while also locking down the head to keep it from moving. The crank is handy, but I found it to be too jerky (it's better used with a motor). I'd rather just push the head with my fingertip for smoother control. Since everything is stainless steel ball bearings these days, the Kessler design delivers crazy smooth & silent moves. I don't mind the belt drive, but I'm worried that the rubber material could break over time (time will tell).
< Mounting the Pocket Dolly to the 504HD fluid head mounting plate with a 3/8" bolt.
I will admit that the slider was a bit too heavy for my Manfrotto 504HD head. So once I mounted the slider directly to the tripod, I had better horizontal results. If you're planning vertical dolly shots, or even more advanced jib-type shots, you will need a fluid head that can handle the 7 pound slider.
The slider comes with a pair of outrigger feet for ground shots, and a nice carrying bag. But, I really wished the shoulder bag had a hand strap (Meh...knitpicking).
Overall, Philip Bloom put his name on this slider for a reason: it screams quality and functionality. It could be my favorite new toy, and I can't wait to shoot more video with it.
If you want to add higher production values to your simple shots, you should purchase the Philip Bloom Signature Series Pocket Dolly. You'll never second guess this well-made dolly slider ($1095).