I paid about £270 for the 600mile service at JHP and found out after wards Ducati Wolverhampton were doing the same thing for the price you quoted - that really pi$$ed me off especially noboby told me you have to complete more than 620 miles so the service symbol (spanner) comes on as it cannot be reset until its actually triggered.So guess what on the way home the bloody symbol lit up.I have a choice to go back or wait for the next service. But for sure i intend to have my R serviced at Wolverhampton in future because a) They are cheaper and b)They are nearer to where i live ,they also offer free collection and delivery service and on top of that Tony is a real nice bloke!
To be honest I'm with FP on this, JHP are pretty much the dogs danglies when it comes to Dukes, what John and Jeff don't know isn't worth knowing.
Saying that I'm sure if you were to point out to them that other Ducati dealers were doing the service for less, I would be sure that they would better the price.
I asked about the first service while buying the bike at DLS, they quoted me the full price, but I managed to get them to include it in the deal, so I just paid for the comsumables which was about £80.