I had the KS eTen dropper, externally routed with remote. Cost around $119 from Jenson i think. I also found a Specialized remote lever in aluminum on ebay (instead of using the included remote from KS), and installed both on a hardtail i had a year ago. It worked great. Though it's tricky to find a good spot with the shifter on the left as well.
I sold off that first mtb a month or 2 later and bought a second, much better hardtail, 1x drive, came with a dropper. I got used to that so very quickly. makes it easy to get on and off, etc. I still have that KS eTen dropper in my box. I've considered putting it on my new gravel bike with 27.2 seat post dimensions, but i've held off.
I don't think PNW makes those droppers. When i was shopping for one, i emailed TransX. Their new one was not in stock, but they suggested i look to PNW's web site for one. All the specs at the time matched TransX's dropper for 27.2. I think it's just rebadged. i THINK.
a dropper with the lever at the seat seems odd. I wonder if it plays well with riding. i'd rather not have to move a hand quickly to the seat as i approach a sketchy section. having the remote near your hand is so much nicer. and efficient. and safer i'd say. but they work best with a 1x drive setup. you can make it work with a 2x, but it takes some finagling to find the right spot.
eric/fresno, ca.