I've stayed twice.
The first time was outer building. It was at a very great discount. It was a very nice room, but I would not have paid rack rate for that room at that time. It was November, and on our last night, very late, we had a 'practice' viewing of the holiday light show on the castle from our balcony. It was a magical way to end our stay. It was also very cool that the holiday deocor went up while we were there. The resort kept transforming overnight.
More recently we stayed in the outer club building. It was also amazing. I really love club level, but maybe not the best way to celebrate weight loss.
You have acccess to an unlimited buffet of food much of the day, and much of it is high glycemic carbs- i.e. the fastest way to put on weight.
On the other hand, much of the club level offerings at breakfast are exactly the kind of foods you probably are already eating: fresh fruit, oatmeal, yogurt (including the plain kind- club level at GF is the ONLY place at WDW I've seen PLAIN yogurt)! They also have SKIM milk if you want it. Other places have skim milk, but sometimes you have to search to find it. You just have to limit yourself. f you can dothat then it's a great option. If the buffet approach is too tempting, I'd pick a regular room - and splurge on the view instead.
Afternoon club offerings are candy, goldfish, chips, cookies. In the evening, they are often classic appetizers like puff pastry with high fat fillings. They also have fresh veggies with dips, and things like salsa. So again, if you have the willpower- then they often have just the kind of food you want. I mean they had really nice fresh veggies like asparagus and grape tomato! (hard to find either ANY other place on property)
Overall the resort is very lovely. It's not my very favorite pool on property, but it is very nice. The view is beautiful. The cabanas on the beach are very nice. the music in the lobby is quite nice.
The one quick serve breakfast we ate the eggs and bacon were really bad. Otherwise the offerings were similar to the lounge, but the lounge offerings were better. Many lounge offerings are bite sized portions.
We really loved the location of the outer club level rooms. they don't have the view, but they were very close to the bus stop, quick serve, and the rest of the dining. Also, it s very close to the quiet pool/hot tub. The only thing that is not super close is the slide pool, and it's not a bad walk.
One other item, when we were there, the monorail was down at least half the time we were there. I've never seen it so bad. I mean literally most days it was down from 10am until 6pm, and late at night. That said, the walk from the TTC to GF is actually not all that far. I think we did it in 22 minutes to our room. The path is not super clearly marked the whole way, but it was kind of pretty. we got to walk past the Poly and the Weding Pavillion. It can be done! (You can not however, walk from MK to GF)
So I would be sure to ask about it before you book.
I also second that the BC/BWK would be great substitutes if you decide to go elsewhere. Both have similar room decor.
The decorations are incredible, not just the gingerbread house but the tree, and the swags on the ceiling, and the light-up white reindeer out on the grass. 
just like Krispy Kreme donuts. 
