Absolutely nothing (yet).
A great all round car.
Even though it's a sporty model the ride isn't too harsh, and the resultant grip and handling are very impressive.
Being a "Plain Jane" Si model it lacks the RSA kit the ST24 has, and a few of the toys, but engine and chassis wise it is identical. This can be a good or bad thing, depending on your viewpoint. It's a mostly good thing in my eyes. It seems to lead to owners of other V6 engined Mondeos being aware of what it is from the few external distinguishing features.
Although I keep hearing that it is a fast car, it is not as fast as I thought it would be, but still pretty rapid. But the effortless way in which it does what it does do never fails to impress. And as for the soundtrack... Although it's not that fast or powerful, I do think it is a great engine, and its design heritage bears this out, as do contemporary reports.
Town-bound fuel consumption can be a little scary, but it's much better on a run. And in any case the noise it makes more than makes up for the penalty at the pumps.
Ford mondeo 20si I bought the car in 2002 and its now clocked 147,000 miles even though only 2.0litre still rapid 0.60 just over 6 sec engine slightly mod, but not much.
Reliability, is near perfect tyres, brakes, wpers that's it in 4 years never failed m.o.t.
Insurance group 12 can be high for younger drivers.