Usually can't go wrong with Cobra. The Fly z or z+ can be had chap but to me they have a hollow feel to them...never solid.
I'd look for something with a sliding vs. Flipping back to front weight if that type of thing interests you.
I had the Ping G30 lst and it was ok but I was never a fan of the sound plus it always felt like I was hitting a rock with it. Distance was fine and so was forgiveness. I just sold it because the forgiveness wasn't a big issue and I found more distance with something just off the rack.
I was talking to Frank at Ace of clubs and he suggested the M2...2016...not the new one...last year's model. He said it's longer. And we know its forgiving. I ended up getting fitted for an M2 which I'll get next week.
In the meantime I traded my Ping even up for last year's M1 with the stock Fuji pro 60 just so I had 2 heads to take the same shaft adapters. I kill the M1...love the feel. I can mess with the weights a bit but it's hot. I know it's not as forgiving as the M2 but it's not my concern. The M2 should be every bit as long.
If forgiveness is not an issue, than either head is great plus u save money being last year's model.