As you said it's only worth what someone is willing to pay. It's a two word domain, reg'd for 7 years. Not particularly high traffic searches. The words are computer centric ie RAM springs to mind but has potential for other uses. Probably most valuable to a business with that name.
Based on similar domain sales I personally (imo) would value it at £50-£75 not included Nominet fees. As the floor appears to fallen of the bottom of UK domains recently. Also consider how much is it worth to you, to sell? Be honest with yourself come up with a figure you would be happy to accept and either go in with that and stick to it or go above and be prepared to haggle.
If you request them to make an offer expect a lowball reply. IMO it's always better as a seller advertising a domain for sale to have a figure ready.
But try Acorn Domains forum for appraisals it's by far the most popular UK Domain discussion forum and there are many people far more knowledgeable than me.