The QP is more than a 4200 due to the way the cats are fastened to the manifolds - the bolts are pointing upwards so access to them is severely restricted, and of course they are rusted solid. If they designed the bolts to face the other way round you could shave a couple of hours off the job.
I strongly advise to have the flywheel, clutch, F1 sensor, magnet, release bearing, spigot bearing and fasteners all changed at the same time - the last thing you want is to be back in there a short time afterwards. I also advise to change the engine mounts whilst the bell housing and cats are off - but make sure they don't break off the subframe bolts as they'll be stuck fast!
Finally, make sure the workshop have the correct diagnostic equipment - they need to perform the DEIS calibration and the PIS auto set as well as the other usual set up parameters that come with a CC clutch change.
I spoke to a specialist who confirmed the clutch was probably on its way out. I'd rather change it a bit early and choose where/when, etc rather than break down and get it trailered to the nearest dealer.
Got a quote from them:
£2100+VAT for the clutch change, covering the clutch, F1 sensor, magnet, release bearing, spigot bearing. Will supply a flywheel if required at additional cost.
It also needs a service. Last done Dec 2014, so may as well have it done by them a little early.
All fluids and 2 year service £800+VAT
May need more doing, such as lambda sensors, etc.
Are these figures about right from an excellent specialist with a strong reputation?