I can only report on what my own experience is where there is no hitching, latency or massive frame variance. The game feels smooth to me. What on earth am I in denial about lol? If my experience was as you suggest with the 'spikes' then I would swap to a 290/X. Remember we aren't all like you lot who are loyal to the brand

. I go with what suits me at the time I am buying.
Being somebody who likes to think he is good at FPS games and has played at a decent level through the years in different games I'd like to think I'm experienced enough to judge if my game is running smoothly or not as the smoothness greatly dictates my effectiveness.
Depending on how things work out over the next few months I'll most probably get an AMD card or two next so I'll make a judgement through experience so I look forward to you lot all giving it the 'PEBKAC' when I don't notice anything different

.