I had a similar mental wrangle when I bought my company car a few months ago. It's a 3 yr old E220CDI with 42k on the clock.
My quote for 15k miles per year was £86.00pcm inc VAT for 3 years. I spoke at length to the contract team about the content of the service+ contract and it works in exactly the same way as my fully managed service that I was used to (minus insurance, tyres and any personal abuse). It's completely worry free for 3 years and includes my MOT, Service costs and any remedial work. I think it's a terrific product as I was very nervous about buying the car and running it outside a cosy company car scheme.
My next service is a D service, which I think is small, but I still feel it's great value for money and I'll probably break even at the end of the 3 years. Even if I don't I'll consider the possible overspend as good peace of mind.
Interestingly though, because I didn't pull my finger out in time I had a 5 week gap between my car being purchased and taking on the new contract. Because of this gap MB insisted I had a full inspection undertaken to identify anything that's about to wear out and not be covered by said warranty (despite being with the same dealer since new and will remain with them for the next 3 years) . And charge me £75.00 + VAT for the pleasure!!! Cheeky gits. I could have probably haggled but I didn't have the time or enthusiasm and just got on with it. Very bitter about that though. I feel slightly better in that I took it in before I bought the car for some 'odd jobs' to be sorted out, inc brakes being changed, tyres replaced for the first MOT etc so it was in tip top condition anyway at no cost to me. Also, because of the break, I couldn't claim for anything for 3 months once the contract was setup. Lucky my service falls outside this...
As I say, I have my first personal service at the end of Sept and I have a couple of snags they need addressing. This'll be my first experience and I'm hoping it's pain and cost free. If not, I'll be having words.
Andy