I own an '08 Springer and just bought a SESG (Spiced Rum). Got about 800 miles on the Street Glide. Have 11,000+ on the Springer.
My Springer is a grin. It's "point and shoot". It's a rocket. I love the way you sit "down and in". I've ridden 1,000 miles over 9 days on the bike on one major trip and 500+/750+ on 2/3 day trips. Comfortable limit for me is 250 miles in a day. I've got a 14" windvest windscreen and the original seat. Less buffetting than w/o a windshield, but still quite a bit. At some level, that's part of the ride. I put a T-Bag on a sissy bar when I travel overnight on the Springer. Day trips I ride w/o the TBag, so you're limited to what you wear and carry in your pockets.
Street Glide is like riding in a big torque high performance sedan. Comfortable. Roomy. Still lot's get up and go. Completely different ride. Put about 400 miles on yesterday, and could've gone a few 100 more. Good part in the twisties. What they say about the frame redesign is true. Handled like a champ. Twisties were fun.
Fairing makes a big difference. Doesn't take all the wind out of the ride (wouldn't want that), but smooths it plenty, especially compared to the Springer. Bags are a real convenience. Rain gear. Tools. Water. All the backup stuff I pack on a longer trip (oil), you can take on regular trips.
Two more points about the SESG. Radio and cruse controle. With the Springer, you ride in solitude. That's the point at some level. But a long ride can get pretty quiet after awhile. I'm enjoying the SESG radio. Cruise control. What a delight. I've riddern those 11,000+ miles on my Springer all with my right hand on the throttle. Cruise is a real convenience. (I tried but never really liked the mechanical thumb screw on the Springer).
My wife doesn't ride on my bike (good and bad, there), but if I were routinely riding two up, I'd go for the SG or another HD touring bike. The Springer is a one-seat sport car, IMO. You can take a passenger short trips around town, but the SG is the better combination of grins and comfort for two people.
In the event, you' can't go wrong. Buy what winds your stem.
Good luck.