I was at my main dealer the other day picking up some parts and over heard the bloke infront. He had an '03 STi which was having low rev hesitation, described as "like kangaroo petrol" The dealer had tried everything to sort it and said they now had four '03 STi's all with the same problem!
They were arranging for some Subaru trouble shooter to come down and look at all the cars at the same time. Anyone else having the same trouble? Four cars all at the same dealer is a bit of a worry!

 

there is a bad flat spot at around 1800rpm with light throttle aplication on the STi8 TypeUK, It was the first thing i noticed when i drove one. It is a problem in the ECU map, the PPP doesnt fix it. The only real fix to this is a remap at the bottom end IMHO.