I have had the Ziexs 225/55/17 on my G35 sedan about 4 1/2 months now, 6-7K miles. These replaced the GoodYear 215/55/17 RSAs that came as OEM (a small side note: in Florida, law enforcement uses RSAs on all their cars).
When comparing the Falkens to the GYs, the Ziexs have:
- better grip in the dry
- much better grip in the wet
- are more comfortable, slightly softer ride
- look very sporty and aggressive, both the sidewall and tread pattern (I like this feature a lot)
- do not balance as well as the GYs, a little shimmy at highway speeds, even after 3 balancing attempts
- are very slightly noisier at speeds 25-55mph, the same above 55mph, but way noisier at speeds below 15mph (in the parking lot)
- are unidirectional (may contribute to the noise), can only rotate front to back on the same side only (e.g. can't switch front right with left rear)
- so far, high wear does not seem to be an issue, but it's still early in the life of the tire
These are only my opinions based upon my personal experience. Another Ziex owner on another board agreed with me mostly but mentioned that his set were not noisy at all; but noise can be a subjective quality. For instance, I think the G35 sedan has too much wind and tire noise intruding, most other owners comment that it's one of the quietest cars they've owned. I think it's quiter than my 96 Altima, but WAY louder than the 02 Acura TL it replaced,... and WAY, WAY noisier compared to the coffin-like silence of a Lexus ES I test drove. But if you like playing your stereo, you may not even notice the tire noise.
Hope this helps... did I leave out anything?