it's been a little while but I believe that some of the features that you would want to do can't be done on the s100, and the cost of upgrading to those later is more than the cost of just getting the s200 up front. also you will need an eprom burner, I use the willem burner. check ebay it's like $40-$60. then just a couple eeproms and your set. You can get the romulator for ease of programming but it's up to you if the cost is worth it. I don't know about crome so I can't say, if mtber is using reccomending it then I'd have to agree, as he is the guru. I have never had issues with my s200 system and I have burned countless maps for my ecu so I can say that hondata is a good choice.