Well, it ran poorly when I bought it, but I thought I knew what it was, so, got it anyway.
The list, Air mass meter replaced, all exhaust sensors, the cats' internals had melted into the exhaust back box, new cats & new back box, new variator solenoid, variable inlet manifold seized and most recently I replaced the piston rings to stop the oil consumption, while I had the head off I reseated and cleaned the valves. That's the short version anyway.
The engine management warning is still on and it's still more sluggish than the almost identical saloon that I had before, which had done nearly three times the mileage.
Poking around this forum, I'm going to try the reset for ECU and throttle to see if it will inject some pizazz into it.