Think excavators are expensive...Just wait! The EU will enforce ISO 12117-2 that specifies ROPS cabs for excavators up to 50 tons, by December 31,2009. I am pretty sure with our ambulence chasing lawyers here, North America will follow suit.
If this is the EOPS standard I think it is, you might not see much cost increase. Volvo (for one) saw this coming and decided to make their standard C Series excavator cab compliant ahead of time, in North America as well as Europe. Safety is a "core value" of the company and they thought it was value-added and decided to lead the market instead of wait for the govt to tell them what to do. C Series have been out 2-3 years now. It definitely added a lot of cost but anything they tried to pass to the market has already been passed. Looking at the cab you wouldn't notice it - it has better visibility than the B Series cab despite being stronger. The pillars are extruded instead of bent/welded sheetmetal like most.