Thank you all, you've been very helpful! I picked up a vial of the 550 today and will be going with that. Here's my recipe, for anyone who is interested. Critiques are welcome.
Butternut Belgian Golden Ale
11 lb. Bohemian Pilsner
1 lb. White Wheat
1 lb. Belgian Candy Sugar
Roasted Butternut Squash (quantity TBD)
1 lb. Rice Hulls
0.5 oz. Magnum - 60 min.
1 oz. EKG - 30 min.
1 oz. Hallertauer - 30 min.
1 oz. Hallertauer - 10 min.
1 oz. Saaz - 5 min.
Mash Target - 148 F
Estimated IBUs (per Beersmith) - 26
This is my take on a pumpkin beer for the year. I hate "pie in a bottle" style pumpkin beers, so I'm going for a subtle squash flavor with no added spices. I'm hoping that the spiciness of a belgian will compliment the squash without overwhelming it. I'm not absolutely sure about my hop schedule. I really hope I don't have too much going on. It also seems like an awful lot of hops to achieve 26 IBUs, in spite of the low AA's.
Brew day is tomorrow and I feel like I've still got a lot of reading to do, especially about how much squash to add and how much gravity I can expect it to add. Beersmith doesn't appear to have the capability to add pumpkin or the like as an ingredient, so I won't know what OG to expect. The recipe without the squash estimates on the far low end of a Belgian Golden Strong Ale (1.070). I figure that if I'm over that by a bit, it'll be fine.
Again, all input is appreciated. You guys rock!