Keymed service is good, but the labour price of £150 per hour (for service of electromed equipment), and £75 per hour travel is unjustified. Their service contract charge on scopes is also high compared to other olympus suppliers in other countries.
We have all our rigid scopes serviced & repaired by a company called Microscopix (tel 01992 469085), who are also a manufacturer.

Their service is very good and a quarter of the cost of keymed.
I have heard that the french olympus agent is far cheaper than Keymed. Keymed may have the lions share here, but not in the rest of Europe and the USA. Pricing for sales and service is far more competetive in those areas. We have just about all keymed equipment, because the consultants don't want to try anything else.
I can't comment on other suppliers.