Ok I have some feedback on this. I have the Rio long midge tip (5' long clear sinking tip), Cortland camo tip (7' sinking camo tip) along with a Rio hover and other sink rate lines.
There are some definite advantages to all the lines listed. Rio midge tip strong points are fishing very shallow water helping keep your fly out of the weeds, also fishing your fly just under the surface like during a callibaetis hatch for example. Also if your fishing nymphs like chironomids you can cast it out and let it slowly fall through the water column. The way the tip sinks with this particular presentation style allows you to slow strip the flies up at an angle that mimic the naturals. You will get way more strikes and hook ups during chironomid hatches doing this vs a hover ir clear intermediate full sink.. It also allows you to feel the hit as opposed to staring at an indicator all day. The running line floats well and can also be an aid in strike detection.
The Cortland line basically does the same thing as the midge tip with one major difference. I've noticed The running line on this is also supposed to float but it will break through the film and stay just under the surface giving you incredible contact with your fly through the entire retrieve, along with eliminating wind drag issues. The hits can be savage with this line. It's great in shallows and shoreline areas as well. The chironomid fishing with this line is also good. It seems that this line tip sinks a little quicker than the Rio midge tip. I don't troll but this line in particular will keep you fly about 3' down while trolling and is deadly when used this way. Hope this helps. I never hit a lake without these lines.
The hover is amazing if your looking to cast and retrieve your fly parallel through the water column. It will continue to sink throughout the retrieve but slowly. So think scuds, damsels, leeches, mergers just under the surface, in 2-6' of water with this line. Also no wind drag and great strike detection.