anyone with these guys? what's it like?
apparantely, for £30 a month you can have unlimited landline calls, unlimited mobile calls and unlimited international landline calls including line rental.
dodgy company or not?

Given the fact that Mercia Telecom is just a trading name (not registered with Companies House) and Richard Douglas Enterprises (the owner of Mercia) has been around less than 2 years....although claiming 20 years telco experience on their website....I would steer clear!! Their are plenty of respectable telcos in the UK to choose from.

An interesting company, but companies house does show some warning signals:

Name & Registered Office:
RICHARD DOUGLAS ENTERPRISES LIMITED
2 HOLLOW CRESCENT
COVENTRY
CV6 1NT
Company No. 05916930


Status: Active - Proposal to Strike off
Date of Incorporation: 25/08/2006

Country of Origin: United Kingdom
Company Type: Private Limited Company
Nature of Business (SIC(03)):
None Supplied
Accounting Reference Date: 31/08
Last Accounts Made Up To: (NO ACCOUNTS FILED)
Next Accounts Due: 25/06/2008
Last Return Made Up To:
Next Return Due: 22/09/2007 OVERDUE

Anything that shows OVERDUE can (but not always) be a warning!!