I've got level 5 everything except Test Track (which is level 1 at the moment). All my research departments are at least Level 2 (£3m each, and the sponsor one is on level 6 (£30m). My lowest component stat is currently 58%, the highest 65%, but it's not quite good enough to replace Ferrenzi overall - I do use my own Monocoque, which saves me a kg and gives me 100% stability.
I love how people can play it so differently. I don't think I'll be in League 6 next year though.
My oldest driver is 17, and has at least 4* in everything