From my research I have found the kit's to make a lot less of a dent in the credit card, the lt-40 kit is more than $40 less than the ARF (on tower it is at least) and from what I've been told the ARF requires glue and everything too because it is not completely assembled. It only makes sense that it would cost less for sig not having to build the plane for you, that extra $40 is basically a charge for labor.