front 1-way, when
1. on-power (throttle) acts like a spool, 4wd, power to all 4 wheels
2. off-power (no-throttle or braking) acts like a rwd only, the front tires will continue to roll forward, this will give your more steering around the corner. however, you cannot brake very hard since only the rear tires will lock up, causing the car to spin out.
For racing, spool is the way to go, as it is the fastest around the track with today's powerful brushless motors and batteries.
For leisure/fun, you can consider 1-way because it will wear a lot less on the belts, drive cups/shafts etc... You have to treat it like a 2wd and DONT slam on the brakes. For a large, flowing track like JV, its quite fun there.