Do not get me wrong they are both very good and very reliable AEG's. Both the G&G and ICS companies are very reliable as well. Each airsoft gun is based on personal preference. If you like to blowback then get a blowback if you don't then don't get one, Stick with what you now and like. I just so happen to like the blowback AEG's and will stand behind them all the way. Both the Blowbacks AEG's from G&G can be upgraded like normal AEG's with some exception.
But yes the GR-16 Blowbacks an excelent AEG as well.