Most people (me included) would advise you to wait for level 59 and buy the Ping G25's. They have been the game changer for players for a long time. While they have a little less forgiveness, they are high trajectory compare to the medium trajectory of the Nikes. Makes a hugh difference due to a softer landing = less roll out. They are also 400 credits cheaper. lvl 59 is around 88K to 89K XP points.
If you do a Forum search on the Ping lvl 59 irons, you will find may threads regarding the recommendation of those irons. I would at least wait until I reached that level. You may have a chance for a 2 hour free rental of them to try them first. I used them until I reached lvl 85 and could buy the Nike's.
Hope this helps.
phred952