As with anything 2nd hand and no longer obtainable new, it's worth exactly what someone will pay for it. mc28's fetching fairly big money (i.e. £4k+) is nothing new but it would appear a couple of people recently have been happy to pay similar figures for mc21's and that is something new.

Whether those sort of prices will filter down to the private market is another matter.

The only way to know is advertise it, see what someone offers, banshee may say it's worth £6k, you may want it to be worth £6k, but if no one will actually pay more than £4.5k for it, that's "all" it's worth.
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