Thank you for the reply. When I spoke to the folk at Evans, they also said they wouldnt recommend a Brompton for a daily commute of 20km and when I rode one, I felt that although they are very well made, it would be difficult doing this regularly over that distance and I feel a 20" bike is a decent compromise. I took my Btwin 500e to Richmond park the other day for a 25km ride and other than a sore arse from the saddle, it felt manageable. The issue is that the 500e is not rated for my body weight and I cannot attach a lock or pannier to it as it will only make it heavier.