Ive owned 2 x Valvers, and 1 x 5 Turbo.
The First Valver never ever went wrong in 1 year of ownership, 2 oil changes, Full exhaust and Air Filter - Car was happy and was great fun, it was only the 2nd car i ever bought so at 18 i thought it was awesome, surprised a lot of people and really enjoyed driving it - i thought it was a great car for a first "fast" car.
Got bored of the power after a while so sold it to buy a Mint reasonably highly tuned 5 Turbo.
It was awesome, loved it - until it went pop.
Great fun when theyre going but they do go wrong - no matter what anyone tells you ;-)
I actually had it all rebuilt, running over 200bhp but my confidence in the engine had gone - i just knew it wouldnt last!
I actually swapped it for a Dimma Clio (Head work, Chip, Cams, Exhaust, Filter etc), was a gorgeous car but just felt soooo sloooow after the R5!
Overall the Clios cost me hardly anything in the time i owned them, but the 5 cost me at least £2000 just in repairs alone.
Thats the biggest difference to me, but then again any highly modded car will go wrong - but id never have got the Clio as quick as the 5!
I sold the Dimma after 3 months and bought a Pulsar GTI-R.
I will own another 5 one day, but it will be running sensible power - and hopefully electronic fuel injection - the biggest problem with them is getting the fuelling right, if its not - it will cost you big time!
Pics:
1st Clio (was a Standard Phase 1 when i got it)
http://www.anything-cars.com/images/CLIOPIC3.jpg
Renault 5 Turbo
http://www.anything-cars.com/images/Mycar2.jpg
Dimma Clio:
http://www.anything-cars.com/images/ClioDimma2.jpg