I think it's a good match. Have heard good reviews. Am also planning to get one for my d80.
The 866 is targetted at the Sb800/sb900. It's more powerful than either of them.
It also has wireless flash commander capability (with TTL), so it really is a "copy-Sb900" in that sense.
it's only slightly more expensive than the sb600, though i think it's a fair bit larger.
I only use a Di466, and it fulfills most of my needs except it doesnt swivel (though it does bounce), which is why im upgrading to Di622.. Unless you are a very heavy user of zoom+flash (and thus need higher Guidenumber)/ you have specific lighting needs (and need wireless commander), might consider one of the smaller models? Esp since i know from using my friend's d5k that the body is quite light... a heavy flash like the Di866 might be quite top-heavy and hard to hold steady for long periods. hope it helps
guys but i heard di622 has no screen. is it easy to change setting and operate the flash in general? this is gonna be my first flash and so im gonna be learning all the things when i get my flash... but the reason why im considering such advanced model is that i dont wanna make mistake of getting the smaller one then after few months when i start i learning everything i regret and start wanting to buy the big one... so i thought why not just buy Di866 straight away... and plus my D5K has battery grip so its much bigger and more stable than D5K without the grip... thats why i thought the size of the di866 will be alright? any thoughts people?