Galen
What does the service charge cover? I think it is about the standard rate for retirement properties. A 15% fee on selling is a lot - especially given that these properties have a niche market and a seller would probably be unlikely to get the price they are expecting.
The meal charge is very reasonable - much cheaper than Meals on Wheels.
Without seeing what the apartments look like and the type of development, it's difficult to judge.
I looked at some small 1 bedroom retirement flats for my mum in Wanstead (an expensive area of East London) a few years ago. They were priced considerably less than non-retirement flats - around £130,000 then but now around £170-190,000. I suppose 2 bedroomed would be around £230-250,000. She didn't like the look of them much and decided against it.
I think if you like the look of them, have very thoroughly investigated the various charges, conditions of residence, etc., can afford it and feel it meets your needs - it's worth considering. I expect living in such a development can relieve a lot of stresses about property maintenance and provide extra support if you need it. You would, of course, need to get legal advice to ensure that there are no disadvantageous conditions tucked away in the contract, and establish by what percentage any fees are allowed to increase.