I went to the G425 after playing JPX 919 tours for two seasons. I just don't have enough time to practice so I needed something forgiving. I have played two rounds with the G425s and these are going to stay in my bag for a while.
They are super forgiving (esp on toe strikes) and the size of the head doesn't bother me much . The offset was a bit annoying the first time I looked at it but I have gotten over it / adjusted to it. According to Arccos, my approach play has improved (by +0.5 SG) over last season and I am hitting 1-2 additional GIRs than normal. I'll take that any day. I havent experienced any jumpers out of the rough and I can hit draws and fades with these without any problem.
The only thing I don't like about these irons so far is the sound/feel. These irons are loud (esp indoors). Outdoors it was harder for me to tell where I was hitting on the face unless I hit excessively on the toe or heel. I am honestly okay with that because these are so forgiving on mis-hits. When I practice on the range, I make sure to carry dr. scholls spray to figure out where my strike patterns are.