My son has a standard length Brava 4.11 and he is a little over 6′ tall. Not a problem with fitment and it is fast. If you are looking at the 2 cycle chassis, one made for 100cc or lighter driver would probably work best. Just make sure you are going to have enough room to mount the clutch inboard as most 2 strokes run outboard and might not offer the proper clearance without modifying the seat mounts. As far as price, the Ignite is probably the best deal at under $4K for a turn key LO206. Comet Kart Sales makes the Eagle which is a good design. It also comes as an extended version and the price is right. The extensions on some karts are just moving the pedals forward and extending the front bumper. The Margay and Eagle have a longer chassis, I believe. I know the Margay does for sure.