Every story has an ending ...
I called the dealer on Monday and explained (complained about) the situation and they reassured me that will do everything possible to have the bike back on the same day. They even offered to book me in on Tuesday (today that is) and said the first service would be at a reduce rate of £65 + parts.
Well the final bill was £124.22 (sounds familiar?) which was their £65 + £26 for oil + £9.28 filter + £2.63 oil disposal + £5.11 grease and brake cleaner (

I wonder how they worked this one out) + 15% VAT ... I need to add £10.60 for my travel card and a day off work.
At least I have a genuine Suzuki stamp o the book in case I might need to use the warranty in some unfortunate event. From the job sheet, it doesn't look like they did anything much other that oil change, lubrication points and fluids checks.
Bottom line, next service I will do it myself as I would expect probably to cost around £200 at the dealer. For this kind of money I would get a very decent oil, genuine parts, nice toolbox, bbq food and beer

while admiring the work ... probably something for the kids as well ...
On the good side ... wow ... 8000 rpm is so much more fun


)
Thank you all for the sensible advice. Much appreciated.
Andy