There's 2 things to be considered here.1. If money is not a problem, and you'd like to extract more out of your engine, then go with the Type R conversion. RSX engine is a wonder kit which can accept any kind of mod upgrades, where as the S2K engine is rather hard to mod. The already high compression ratio of S2K engine prohibits any kind of force induction mod upgrade except if you go for the lengthy process of lowering down the compression ratio. Ask around your local mechanics, they can easily extract 40bhp more from the RSX with naturally aspirated way.2. If you prefer handling rather than outright power, go with the S2K. It is one of few that can be categorized as a front midship rear drive vehicle like Mercedes SLR. It has its engine placed on top of the front wheel, giving a perfect balance on high speed driving.So which one you prefer, handling or extracting the best out of an engine? One thing to note though, S2K are known to be not urban friendly because it has a high strung engine you need to "row" the gear to keep it on its powerband.