I can't believe everyone thinks they are good on petrol =0 Mine does an average of around 19mpg cruising speed, and foot down as low as 9mpg =/ Of course a few tasteful mods (e.g uprated fuel pump, FSE boost valve, remap, chipped, Kent cams and verniers, 4-2-1 manifold with 3 inch decatted/deboxed straight through exhaust pipe.)
I will agree that they are fun, and I will also add addictive, as I've had many shall we say quick (ish) cars, but at 171bhp and weighing a nibble under 930kg, it's a pocket rocket, which you can enjoy to next levels on a good old track day, going past cars that would even shock yourself.
I also saw that the gearbox has been noted. I will also expand on that; I have owned this car for around the year and half marker, and have had cir-clip replaced 3 times (new 1 needed again as no drive) and replaced the gearbox once as the diff well, let's say broke =0. Needless to say, the gearboxes are naff, which is a common fault amount the valvers, Williams and anything else that shares a JC5 gearbox, as it's a clipped diff rather than bolted. It does not mean that there is no hope, and you have to live in fear as it can be solved by buying a LSD (Limited Slip Differential) which is bolted to the box. Costing around £700.. OUCH, but last time a gearbox issue will occur IMO..
Another common fault is with the rear arches; they are prone to a lil rust, and if you're stupid enough to lower it 60mm all round with 17 inch alloys, then you may experience more rust than others, which I found out the hard way =( But not as such an expensive fix at a half decent body shop.
Oh, I also have the occasional drip from the sunroof. Nout serious unless you have to replace the seal, then it's an expensive game (so I've been told).
Small note also mentioned by someone above; insurance, it's so far cheaper than my Tomcat, which is a 1.6 on the books with a fair few mods, but no more than the Clio, and it costs less than half =0 Cheaper than my old RS Turbo, which to be honest you're getting a lot of power in the Clios in comparison to the RS as any valver owner will tell you, RST's for breakfast =) My insurance to give you an idea is a couple of pound over £550 that's fully comp insured for 3500 with my girlfriend also.
I'm 21 and live in a semi decent estate (that also covers all cosmetic modifications and audio ;) )
To conclude, if buying / thinking of buying, always remember to do your checks on it before handing over cash, as this is by no way a problem free car to purchase, but in my opinion you would not be disappointed with the purchase =) As I think all in all, it's a comfy, quick, stylish little car that you can easy turn with a few mods and a bit of cash into an extremely aggressive car. Or just leave it how it is standard to be as calm and collected as a puppy on a lead. But remember what happens when you take the lead off!! =)
Hope this helps all, thanks for reading.