the question goes back to mutt's suggestion.
what space do you want to cover and what weather is anticipated. the 604/5 has 41,000 ceiling and others 51,000.
my suggestion is to do a simple matrix xls(not cessna) and just compare the variables. the numbers will speak their own language and you will be able to do a qualified decision based on facts not emotions (falcon vs. gulf stream vs......)
a similar exercise some time ago was done and for a typical 3,000 leg if need be the choice was a lr60xr with a stop and travel first class for longer legs. it proved almost perfect choice, but again it differs between egos.