Re: Now that ElReg is...
Buy the kit - much more fun, and you get to know the car.
I built mine about 8 years ago, and it took me about 2 months in evenings, weekends, and about 8 days off work. At the time they reckoned 80-100 hours for someone with basic engineering skills, and with everything being new it's all relatively easy - really big boy's Meccano (although with slightly fewer pictures than ideal in the build instructions).
I've still got the car and it still makes me smile when I drive it.