If you are running on a slippery track regularly and/or prefer to let your car roll rather than brake hard before entering a turn, you might actually like the 4-gear, but if you are looking for more on-power steering and corner speed, I doubt it will help you.
If you are looking for corner speed an are a die-hard TLR/Losi fan, I'd say wait for the 4.0 and don't put too much money into the 3.0 any more. Other than that you could be happy with YZ-2 CA, Schumacher KC or the like right now. I really found test drives helpful in the past, in fact a test ride made me buy the YZ-2 when I was set not to buy a new kit for another half year or so back in the day...
