Is the "performance chip" for a 2002 honda civic worth the money or is it a rip off? does it cause less mpg?

I also have an 02 civic Si coupe its and i have a chip can't remember the brand but i found it made a fair difference i was told that when you are buying a chip spend a decent amount of money not the cheap promise of more power i have a a DC 4-1 header with a high performance cat and the skunk2 exhaust and a custom made stainless cold air intake(thanks to my buddy)with a K&N filter i did that all at once and definitly noticed more power,then i put Msd ignition ,mass airflow and also changed my pulleys not the biggest powergain but at this point i was kinda hard to tell how much!!! it is also lowered on coilovers with a DC tower bar(strut bar) in the front and rear and a lower to tie it all together i also did beef up the rear swaybar not sure the brand but definitly helped the backend for body roll the front i left and hasn't bugged me yet barely any roll!!!! it all comes down to what your looking for all these performance parts i put on defintly changed my Mpg by a a fair bit say an average of 75 - 100km but its hard to really say how much cause when you have all those goodies you definitly drive different higher rpms alot more downshifting and of course opening it up every now and then only up to the speed limit of course!!! my suggestion to you is to start small air intake/filter,chip and tighten up the suspension if your keeping the suspensionn stock a beefier sway bar and some strut =bars will help body roll and try doing it within a decent budget some parts are definitly worth spending a bit more money on for example a $25 sway bar looks good but isn't functioning it looks cool!!! and always remember that all the money you put into your car is hard to get back when/if you sell it so keep as much of the stock stuff as you can incase you want to put it back on in the future!!! hope i helped a bit and wish you all the best in whatever you decide to do with your Civic Goodluck and Enjoy!!!

Those performance chips are a big question mark. Kinda like do UFO's exist? Does Big Foot really live? Do performance chips really work? Some people will swear by them, some will say they're crap and waste of money. Some of those "chips" such as are available on ebay are just some kind of resistor or diode, that really doesn't do much. But they are pretty cheap to try. Might not hurt. I have a beatup 1991 Geo Prizm with 240K miles on it. It's well worn and well used. I installed some Bosche "Plus 2" plugs and noticed a very nice and noticeable power acceleration over the whole band. It wasn't super huge, but noticeable, even gained 3 mpg in town!! So if the 2-prong plugs did that to my car---because it burns the gas vapor better---would the 4-prong Bosche do better and give more power? I don't know. Haven't tried it. But wanted to mention that.