And in addition to the things mentioned above....
for those people that are like me- ultimatley the car gets turned into a 100% racecar (replaced by another daily driver that will ultimatley have the same fate)...
the car is a better platform to start with (mentioned in the above post) as it already has "performance goodies" like the lsd that you won't have to buy later....but also it lacks a sunroof (that is bad weight, less rigid, and has to be removed for most serious road racing classes), lacks the absurd amount of sound deadening material (more bad weight + its a pain in the a** to remove)...etc...
most things that come stock on a type r can be done/added to another integra, but with a bunch more time and $ that just buying a type R....
and theres the "priceless" pure satisfaction of owning a limited run "real type R"...that no modified non-r integra owner will experience...