Chip mod - is it worth it?

[Lux]

I highly doubt a chip is going to give you 10% hp increase. Especially dealing with OBD-II cars.

More aggressive timing will get you a few hp, but only if you run the appropriate octane. 91 octane here in CA isn't going to cut it. The minute it starts pinging timing will get retarded. Wonder how many of these tuners' dyno runs were done on 100 octane gas?