Yup. If you don't know what you're doing, just don't mess with it. Unless you're an electronics whiz, it looks like you'll have to spend about 100 bucks on a daughterboard, 50 bucks on a willem eprom burner on ebay, another 30 bucks on eeproms, and then you have to know how to tune. For all of the effort involved, it's probably something only the diy-or-death type will want to pursue. I happen to be the diy type- I tune my car with rom tuning, but to be able to do so I had to spend dozens of hours reading through 2500 messages on the dsm-ecu list, through hundreds of pages of reference material on my ecu, and I'm still only one or two steps up from n00b status when it comes to interpreting and modifying the code in the ecu. The nissan guys should be thankful this gui exists, in the dsm community all of the editing is still done with winhex I made excel spreadsheets for fuel and timing, those are my gui. Honda guys are lightyears ahead, they have multiple gui's and a large user base, hell, Vertigo on this forum is creator of one of the widely used programs, Uberdata.