tires

Avoid silicone based products, they are rather harmful, although it might seem different at first sight.

The long hydrocarbon chains that make up the rubber of the tires are attacked by both ultraviolet rays and ozone. As the molecules break up, the rubber loses its elasticity. The manufacturers use carbon black to protect the rubber against UV rays (this is why we only have black tires). A wax based protector is also used: as the tire rolls on the road, additional wax is forced to the surface and absorbes the harmful effects of ozone.

A tough question. It depends on your requirements, driving habits and, last but not least, the amount of money you are ready to spend. Many of us find Michelin tires to outperform other brands mainly because their different, softer composition is better suited to the suspension and riding characteristics of Citroëns. I also found them to last much longer than, for instance, the Pirelli tires of the same price and performance class I had on the car before. But all that having been said, you will find other BXers who left Michelin for another make and don't regret their choice.