Well, I got my Stilo back today (also needed a new Lambda sensor, old one fused inside the old cat).
Workshop bloke at Uncle Arnolds says they spent a total of 8 hours on it but only charged for 3!
Anyway it passed the emissions test no problem and I got my MOT.
So back on the road again.
Think I'll wait a while before taking it back in to get the front suspension recall done.