I think I know a bit of what you're talking about. I have a bicycle on hold with a downpayment on it right now and when I test rode it I thought it was too big at first - it felt huge! It is the size that is "supposed" to fit me and I really liked the bike so I went for it. I figure it's mostly due to me currently riding a mountain bike that is way too small for me, and my previous bike was also on the small side. Pretty sure there's going to be a bit of an adjustment, but I think in the end I will be happy with the size.

Mine isn't the Surly Disc Trucker, it is the Bombtrack Beyond - more of an "Adventure" tourer than a standard tourer. Picking it up next week - c'mon payday!