Could always take your cars to Centre Gravity in Coventry.. but seeing as they usually maintain cars worth 400x the price of an Omega, don't expect to walk out with change from £400

The health check alone is £200, which includes:
Road test & report
Suspension test & report
Weight pre-load to spec
Tyre data check & adjust
Ride height check & report
Geometry check & report
Physical inspection of:
Dampers
Springs
Bushes & ball joints
Steering rack
ARB bushes & drop links
Tyre wear issues
Full setup would include:
Ride height
Camber
Caster
Toe
Bump & Rebound
Road test
From what they do you can tell they're used to working on things slightly more exotic than your average road car

That said I know at least three people who've been there to have their cars set up - a 911 997.2, 911 997 w/ aftermarket suspension, Kirkham 427 S/C Cobra w/ original spec suspension and a BMW 645 w/ aftermarket suspension - and all of them rate the place very highly indeed.
Or throw £70 at the tyre place down the road and watch them like a hawk, as Al says.