These are a new model of irons, even though the X-18 name has been used before, the 'R' do not have a through bore hosel. This change means that these irons have a slightly longer hosel than the X-18 of old. This set also does not have the undercut cavity of the X-20, and X-22, although after hitting the 20's and 22's, I did not see a big enough difference to justify the hundreds of dollars in added cost. These are very nice irons!
Very easy to hit, They have a very soft feel, also these irons are long, 1 to 2 clubs longer than my old Ping I3 blades
The grips could be of better quality
These are very nice irons, and for the price they are unbeatable. The construction quality of Callaway equipment is unmatched and these irons are no exception.