Here's a review of an '04 MINI compared to a the first year production car from Frank:
I took delivery Friday night and have put nearly 300 miles in 5 days of motoring. When I went to pick up the car I was expecting to get the rumored 3 button key design and the sharkfin radio antenna, but it turns out to be that the key is identical to the one supplied in the 2003's and the radio antenna is the same mast design as before (Which I like because it gives the car that Toy Remote Control car look).
However, I can tell you that the build quality has improved significantly over the 2002's. For example, the rear hatch opening area now has extra 2 rubber stoppers located in the lower part of the opening. these rubber stoppers allow the hatch door to close much more smoothly (No need to slam it) and also prevent the development of rattles in the latch area. The Latch mechanism itself works better too.
The frameless windows no longer “Wooble” as they do in the 2002's. When you open the door, the door itself feels more solid and the glass does not vibrate when you open the door. I am glad MINI fixed this because it gave a look quality feel to the car. The rear boot 12 Volt power point has also made a comeback for the '04 model year (It was offered in '02 and discontinued in '03).
The programming of the central locking system seems to be working better. MINI has also installed rubber pads under the bonnet to prevent the paint rubbing problem first reported by Gabe a few months ago.
The new suspension shocks give a more supple, less jerky ride than the '02's but none of that hallmark MINI handling has been lost in the transition. I now find my '02 Cooper CVT with standard suspension and 15″ Continental tires to have a harsher ride quality than my '04 MCS equipped with SS+ suspension and 16″ Dunlop runflats.
Thanks Frank! If anyone else has other '04 observations feel free to post them in the comments.