I am looking for a Brompton bag for daily commuting that is compatible with S type handlebars and the standard LED front light. I saw C and S bags are marked as not suitable for S handlebars and that got me thinking. I will need to carry, say, a 14" laptop and the equivalent of 2-3 books. Any ideas please? A while back I remember thieves on mopeds stealing your panniers in traffic was quite common in London. Is that a concern with these bags? Thanks.