I am looking to upgrade the bike's crank set/shifter/rear mech with Shimano Saint components, specifically the M820's. This is the first time that I am upgrading the bike and I'd like some advice on how best to proceed. I'd like to convert the bike into a full-fledged ten speed. For the Crankset, this is what I had in mind...

Current: Shimano FC-M430, Octalink spline, replaceable rings, S: 170mm, others: 175mm
Upgrade: Shimano Saint M820 175mm

The only part that I am unsure of is the cassette and chain. I know that any 10 speed cassette from Shimano will do (I have my eye on the Shimano XT M771 10 Speed MTB Cassette), but I'd like to hear from the community and find out if there is another particular Shimano cassette that you prefer and recommend.

Any advice, and or recommendations is greatly appreciated.