I acquired a Stateline about 3 weeks ago. From what I understand, it is the same as the Interstate without the windscreen and bags. The saddle can wear on you fairly quickly but there are remedies for that (gel pad, after market seat, Alaska leather sheepskin butt-pad etc.). I'm going to order a Mustang saddle and see what happens, but until then, I have so much fun on this little bike that I don't look at the saddle as a negative.
I went from a Goldwing to the Stateline, so I went in expecting virtually no comfort in comparison. I was surprised that the saddle was the only thing with a major comfort change, but even at that, the saddle is better than I thought it would be.
My longest ride (with a lot of stops, which helps) was 50 miles around town. I had some soreness but never went numb anywhere. I would imagine that the interstate will be good for a longer ride before soreness creeps in because you will not have to press into the back of the saddle to compensate for the wind.
These are really fun bikes as long as you think of them as a cruiser and not a touring bike.
After owning 7 gold wings, some with trailers, some with side cars- and having been used to armchair touring, I dropped out of riding for awhile and persued other passions. But alas the time came when I needed two wheels again so I heard about the Interstate and went to the dealer to "just look". Two hours later new helmet and new bike and down the road. OMG first 20 miles I wanted to turn it around and give it back due to the hard ride and wind buffeting over the shield. Not like my 80, 81, 83, 84 Interstates at all. But something told me to be patient and now after 1,000 miles we are becoming as one. I am amazed how the ride has changed for the better, and the looks and comments I get on the road! In traffic, "hey what is that? A Harley? No it's a Honda. Really are you kidding, that's sweet. A new saddle definitely in the works even though I could probably get by ok with the stock one, but all you guys that put on the Corbin made me jealous.