I very nearly bought a Global Lights instead, the concept is similar to a Radical. I had a long chat at last years opener at Brands with the guy who'd bought the rights to the manufacture, and who was advertising the championship as having a full Tuscan drive as 1st prize. Bought new they were cheaper than Radicals, but not hugely (£16k+VAT). Most of the drivers had early cars, which were looking a bit rough. They got their lap times down this year by allowing proper brakes (the old ones were inadequate kart jobs), trick dampers and few other chassis tweaks - the engine (600cc Yamaha) was the same. I imagine they are big fun, but I plumped for Radical as I was more convinced of the long term prospects, and they could be more readily used in other championships. Only 20 or so Lights had been made over about 4 years (dreadful marketing by the founder, I remember the early glossy handouts from Autosport show pictured a car with bits of tank-tape on it). The championship this year was dominated by one or two cars, run by the owner (since changed, I believe). It was a pity for them - the concept is great, but they've been recovering from poor management at the beginning ever since, whereas Radical got it spot on right away - one of the co-owners is a marketing man who knows what he's doing - almost every Autosport has a Radical mention somewhere. It may be cynical but it keeps a championship alive which protects your investment in the car.
The other thing I didn't like about G.Lights was rolling starts....I love standing starts, biggest buzz in the world.
re sequential boxes...the Prosport Suzuki installation has the shift the other way around causing expensive confusion for Clubsport drivers trying out the Prosport, so much so that you can now buy a kit for either model that reverses the shift pattern
Steve