the mileage doesn't bother me too much, but it is a 6 year old bike and the price (north of 4 k kit and kaboodle) sounds a bit steep.
Let me offer a comparison.
At the toy store, to get a tire, there was a 2002 Kawasaki zzr1200; mind you, it had some 35 k on the clock, but it does have 1200 cc with 160 hp and a top speed of about the same.
Value for that bike? Just over 5 k.
Twice the bike in nearly every way (including mileage, but on a bigger engine that becomes a bit less of an issue) for barely $1,000 more.
If, however, there is a warranty still involved (unlikely) it would be a bit more tempting.