Info from Peak Performance Tyres;
The V rated tyre is rated to 149mph, Speed ratings are in no way to do with "performance" but, not being what the clio comes with as standard, If you had an accident + the insurance company were being picky, It could invalidate your insurance.
The clio comes with the W rating as they can exceed the 149mph mark of the V. But not the 168mph covered by fitting a W.
As for the load rating, It doesn't really matter. You cant really get a tyre in this size that isn't suitable for the clio. 87 being 545KG and 91 being rated to 600KG.