As already stated, none of the current kits are a real challenge! The challenge comes when you start to "improve" the kit, as has been done to the 42009 crane and is now being done to the Volvo loader.
I'm new to Lego and Technic and especially to navigating around the web sits. I've built the 350 loader and was not impressed with its performance. Finding your information gives me hope that I can turn it into a descent model and not an expensive box of parts. Where can I get the parts list and PLEASE make the instruction for your 350 available.