Yay, another member of club chris!

Just adding to some of the comments above, the 6006 is not 3 units like it looks, behind the facia its a massive cube thing as tall and as wide as you'd imagine. I know some people have had problems with it and changed it. Personally I don't think its bad for a unit that comes with the car, and wouldn't think about changing it unless I was to start having trouble with it, as much as anything because I suspect it would be quite fiddly to do.
With the ESP, I wouldn't bother with it especially with the reflex pack pushing the cost up further. I find the handling good enough as it is, and I know that if I had it fitted I would have it switched off more often than on, but that may be down to the way I drive. Perhaps someone who has it fitted could share some comments?
I'll have to agree to differ with Parksey here about the full leather seats here. I just think they are a tad too expensive, feel the way the partial leather and fabrics go together fits the st well, and just wonder if full leather seats will get a little sticky in hot weather.
Hope some of this helps.