Had a company car for nearly twenty years and felt a little nervous going back into doing it all myself. Once I took the plunge though, I never really noticed the difference.
My plan was to spend every penny of my cash alternative on the car so that it didn't start to become part of my salary. Went on a PCP for three years which included a full maintenance contract for tyres, batteries, exhausts, tax etc... then bought the car outright at the end of that three years on a standard bank loan (reasonably low interest).
The way I look at it, when you have a company car it just gets sent back every two or three years and you have nothing to show for it. Once opted out, the car I've got will be bought and paid for after 6 years. I'm quite fortunate though, I opted out aroiund the same time that I got a European role so all my business mileage was a trip to the airport, park the car for a week then drive it back home. I've now got a World wide role which I only need the internet, email and phone with the occasional trip to San Francisco.
As a result, I've got a 4 year old Volvo C70 Convertible which is just going for it's 30,000 service and MOT next week. It still looks and drives like a new car.
Volvo's in general and convertibles in particular seem to have really low depreciation and, because I don't do many miles in it, the residual value is quite high. So at the end of my six years I will own the car outright and it will still be worth 8-10K. Basically, the company will have bought it for me and taken the depreciation hit. I could sell it at that point and put a hefty deposit down on another one, or just keep it. It's not the sort of car that I get tired of driving and it's still quite stylish. I've also got a theory that new cars look cool, then when they're 10 years old they look dated, then when they're 20 years old they look cool again. So who knows I may just keep it forever.
It's a top-down cruiser type of car, not a performance car, but I've got a bike for that, and in a couple of years time when the car is paid for I'll be looking to spend my company car allowance on something around the £15-20K mark....Hmmmmm....wasn't their some rumour about the cooking version of the Desmosedici coming out in 2007? | 
