Definitely can handle big distances - week before last I knocked off a 3 day 2900k blast from Sydney to the Great Ocean Road (a little past Melbourne), including a lap of the Snowy Mountains. All just names to you I'm sure, but probably some of the best riding in Oz.
Final day was around 1650ks (and a slightly ridiculous 18hrs or so), and the next day I felt fine - so fine that all I wanted to do was go for a ride...
I'll write up a ride report in the next few weeks.