Agreed, do the valve service now.
I'm assuming your 25k is miles, not Kilometres, and if so it should have had two valve checks/services since new.
I have a 99 and it now has 60,000km on the clock. When I bought it (from a mate - Bad move) he said that he had never worried about a valve service because according to his mechanic it "sounded OK" I put it in for the 40,000 (24k miles) and they "Said they did the valve service, but they didn't need much adjustment/shimming. At the next service after another 20,000km (12k miles) I discovered to my horror, that the valves had NEVER been touched ever. The clearances were so huge there was minor 'tapping' damage inside the rocker cover. If left for much longer it would result in having to do a complete head recondition. The mechanic who supposedly did the job at 40k skipped town not loing after so I have no recourse there at all.
So, don't rely on what anyone tells you about your engine, not even the mechanics. If you can do it yourself, do it and do it on a regular basis for your own peace of mind and the longevity of your engine.
Mick