For me I bought it on the day of release and despite the bugs I am still enjoying the game. I'm glad I bought it when I did and I think that it's the most fun i've had playing a strategy game for ages.

The game has even given me a few of those OMG moments when you find that you are being out fought by the AI. (it doesn't happen all the time but it does happen ) - Great

If you wait till it goes 'Gold' you will be missing out on months of fun (maybe with a little frustration) but I think its worth it.