Before the Lev or the Reverb, there was the Gravity Dropper.
You ever wonder why you don't see DH racers with their seatpost extended XC style with 8 or 9 inches above the clamp? You get tons of power when you have optimal extension in the seated position. Why doesn't the DH crowd take full advantage of that with a high post? It's because one of the first things you learn riding DH is that lowering your center of gravity drastically improves handling. It also lowers your chance of launching OTB. Being way ahead of the curve (a curve taken at full speed due to their low center of gravity) Gravity Dropper was one of the first companies to manufacture and market an adjustable post. The Turbo LP is their latest offering.
Got a quick release seatpost clamp on your bike? Replace it with a clamp that works better for a dropper post here. Seatpost Clamps.
Initial impressions of this seatpost were that the cable release coming straight out of the rear is silly. They need to figure out another way to do this. Regardless, the rest of the post seemed to be of good quality. I installed it on my 2014 Specialized Crave, and the design of the seatpost clamp would not allow me to level the seat. It was absolutely maxed out with the front of the seat pointing up at a slight angle. I contacted Gravity Dropper and David was initially helpful. He said they had a different seatpost that had an angled hole, and it would solve my problem. After not receiving tracking info for 3 days, I called them and it turns out they did not in fact have that part. They had not sent me anything, nor had they attempted to contact me to let me know. After this, after there was no longer an easy fix, David was unhelpful. Shortly after that, completely unresponsive. So beware! This post will not work on some bicycles with certain seat tube angles, 73 degrees on my bike. Gravity Dropper customer service was poor in my experience. I had to pay initial, and return shipping out of my own pocket, around $30 to figure out that this post did not fit on my standard Specialized bike.
Awesome. Install was simple. I don't know why you would ride without one. FYI, make sure a 400mm post will fit you and your bike. Its pretty long. Also, this comes with a left hand remote only. This means it will be on top of the bars on the left or under the bars if you mount it on the right side. Highly recommended.