The jump from the 4 to the 5 is fairly gigantic. The 5 has more than 2x the CPU and GPU power. The 6 will most likely just use the same CPU and GPU, but be clock bumped a bit, probably to 1GHz (maybe MAYBE to 1.2 or something like that, but probably just 25% faster). So if you're saying you have a 5 and want faster, the 6 won't be much better. The jump from a 4 to a 6 will be pretty huge though. I'm guessing the 6 will have 1GB too, which should help speed things up also.