Search the archives on injectors. There has been a lot of discussion on this issue. You can also send your injectors to a company in the Northwest to have them rebuilt for $25.00 plus shipping. I don't have the web address handy, but you can search the web for injectors and should be able to find it. If I find it, I will post it later.
In my opinion if you can bear the expense, go with Nissan injectors. My .02 worth.
Courtesy Nissan give a discount if you mention this web site, I think.