I have a tall boy seat. Much much better than stock. I cannot stand sitting on the tank, the tall boy will sit you back about 2" and I don't remember for sure but I think it lowers you 1/2" too. Like stated above it does reduce the passenger seating area. The back of the seat still bolts down in the same place, so what you gain the passenger loses. The comfort is nothing special, but it does get the rider off the tank.

 

On the newer models 07-12 I understand the seat goes back 2" but on an 05 electroglide like mine the tall boy on goes back 1/2". Is anyone using the Tallboy on and older scooter? Wanted to know if the 1/2" makes that much difference. I am 6'1" and 190 and the stock seat gives me leg cramps after about 200 miles.

 

6'6", 36" inseam and 36" sleeve.
Find a dealer with a full-on fit shop. Even a softail frame will give you an idea what to expect.
For me, the stock seat put my knees into my wrists in tight turns and my gnads one quick-stop away from making me a soprano. The tallboy seat helped significantly , but it isn't like plopping down in my favorite recliner. I prefer riding upright, so it is a great fit when coupled with my pegs in line the engine guard.

 

Harley seats suck. Check out the Mustang super touring seat. It moves you back 1.5". I am 6'4" and it made a huge difference. Plus, it is way more comfortable than any seat made by Harley.