The ARCC seems to be one of the best engineered Brompton conversions but the cost is high compared to say the Nano.
As far as I can see the only advantage of a Brompton is that it can be folded up. If you need to be able to fold a bike up (as I did when I used one for train/bike commuting) then they are pretty much unbeatable, but the price you pay is very high indeed, both in monetary and functional terms.
A Brompton with ARCC kit is going to be around the £3k mark, easily enough for a very well-specced pedelec that will outperform a Brompton in every way. These days my Brompton sits in the shed, I haven't ridden it for years.
