After even more frustration in getting tyres I want for my 18" alloys, I'm going to look to get some smaller wheels, either 15" or 16". Financially, it works out cheaper than paying almost twice as much for premium tyres. I've a TD4 Sport facelift, is there anything I need to be careful of when looking for smaller wheel sizes? For example I was told the Sport has slightly lower suspension than the standard FL1, and what tyre dimensions do you recommend?