If you KNOW you are going to continue training, then the 2 hour flight is a really good thing to do. You'll get alot more out of it.
It's a bit of a discount too, most flight schools will charge anywhere from $80(C-152) - $140 (C-172SP) per hour for airplane and instructor, so $185 for 2 hour flight is reasonable.
What do they do for the 2 hours flight? I couldn't find anything on it on their site?
I would go for the 2 hour though.