My car weighed 1445kg, with my lightweight seats in it, but with some slightly heavier stereo kit - and a full tank of fuel.
@The Pits is correct I foolishly thought that when Lotus said "1395kg with a full tank of fuel" they meant "1395kg with a full tank of fuel" not "1395 with no fuel at all". (/sarcasm)
At this kind of weight I think 20-25kg out is perfectly acceptable, 50kg for a company who claims "light is right" is not. However, I think we all know where these slightly optimistic numbers came from and I have to applaud the Lotus team for updating their website with more realistic figures and ditching their somewhat disingenuous practice of using a mix of wet and dry weights. The fact is Jonny's 430 IS a genuine 80KG lighter than my old car, and that is impressive considering how well refined the 430s still are, and the extra kit they carry (oil cooler etc as mentioned).
If you want to see some factory numbers which are hilariously inaccurate, look up the modern breed of Astons, or Lamborghinis.