I was in a similar situation a couple of months back. I came from riding a 10 year old GT hardtail.
When I bought a Trek 8.6 DS it felt kind of strange. Really rigid feeling ride. And of course the gearing is much higher.
I have done over 800 miles on the bike now, and enjoyed everyone of them. The bike feels really solidly built and fast.
Its probable that it may feel odd riding a new bike being so used to riding your old one, plus factoring in doubt that creeps into somebody's mind when making an expensive purchase.
In my personal experience the DS felt great from the off. And feels even better now my fitness and leg strength is improving since coming from my old MTB.
Would be good to hear how you're getting on with the bike after a few more miles.