With the 2500k you should be pretty comparable to my setup - I've got a 3570k. I reckon you should be fine unless the issues in Insurgency are more software related or just random.
As for the refunds, I heard a while back that as it's still in beta that doesn't apply and that you can refund any time in the beta period. Worth double checking though. Either way I'd say 2 hours should be enough to confirm whether you have major performance issues - if you do just refund and revisit it another time?
As for the refunds, I heard a while back that as it's still in beta that doesn't apply and that you can refund any time in the beta period. Worth double checking though. Either way I'd say 2 hours should be enough to confirm whether you have major performance issues - if you do just refund and revisit it another time?