Street glide is my next ride. Im 27... i dont do many long trips right now. I have a slim and will have it for a while. If you are going on longer rides i say glide. Or getting up there in age.
Street glides are nice for long rides but you may also consider a heritage. IMO the heritage is good for around town and the long haul. A street glide for me would be a bit heavy for just around town trips.
That's what I always tell people! "Baggers are cool, you can ride all the way there and be totally comfortable, but once you got there you wish you were on your cool bike. Should just tough it out."
I traded my 07 Night Train for my 09 SG and haven't regretted it. The Night Train was fun, don't get me wrong, I loved that bike, but I do 50/50 town and highway riding so I went for comfort on the long trips. Rode the Night Train to Sturgis 800 mi one way and traded it in on the SG 3 days after I got home.
My thought is do what you want to do, and if you realize you want to change your mind, you can always do that too, it is a little costly but sometimes we pay just to find out where our hearts really are .