I got given the whole day package for my 40 a few weeks ago. I went for the whole day in the RS2000. It was fairly eye watering, price-wise, at just under a grand, but in honesty, it was fabulous.
Just me, the car and instructor all day - sole use of the track, so we had no restrictions and were in and out of the car all day - I drove so much that I ached like hell the next day!
I've been driving for years and have done a lot of no limits circuit track days in some quick stuff, but very quickly learnt that I couldn't drive a rally car for s..t!
By the end of the day, I think that I was doing ok - the instructor said 'in the top 2 or 3 % of newbies', so I was quite chuffed (even though he was probably flattering me!).
If you do get the chance, grab it.