Funny you should post on the subject as I've just listed the higher spec special edition Helios XX on the 'For Trade' thread!
The Helios XX hails from 2003-4. The SL is still a lightweight sub 8kg version and its's a very very nice road-bike with an upright ride. The handlebars can be modded to provide a more streamlined position if required. It folds quite compact because of its super-slim profile, is a breeze to carry and is quite fast. I've seen the SL in great condiiton go for over £400 on ebay.co.uk around 6 months ago. Still a coveted bike for some. The previous poster is absolutely correct that is the forerunner to the Mu SL and it is ironically lighter bby around 1kg. Many would say the Mu SL compensates for this with a stiffer frame etc but it is simply a trade-off and matter of preference. It must be a rarity to find a new one in an LBS and it is a fine bike indeed. What price were they looking for it?
Here is a pic of my Helios XX below. They are very similar in most respects except for some specific high-end components. Mind you the SL is still very much a high-end and one of the lightest folders ever made.
