Better to drink it while it's fresh, IMO. Once it's been roasted, the clock starts ticking. I prefer to drink coffee that's within a couple of weeks of roasting. But depending on how it's stored, I wouldn't want to use beans that are much past 2 months.
I will occasionally splurge on a more expensive bean, but generally, I've found that really good, high quality beans will be in the $5-$8/lbs range, about half what they would cost if you bought them roasted in a cafe or grocery store.
Kona is good. But I'm not a $25/lbs coffee guy.