It's up to you none of the armors give any type of bonus so you should just pick the ones that look best to you. I personally mix and patch different pieces.
Hayabusa
All the armor are the same it's just the way how you want to look WRONG! the best armor in halo 3 is the recon armor and you have to be a member of bungie OR get all 7 vidmasters in halo 3 ODST
http://hubpages.com/hub/Halo-3-Armor
No, there is no armor in Halo 3 that has a knife in the shoulder.
No, halo 3 forge is not offline, you may play it online with friends or others.
get a job at bungie.
There is no Brute armor in Halo 3, only Elite and Spartan models.
You can get 43 achievements offline on halo 3 im not sure on odst.
go to http://hubpages.com/hub/Halo-3-Armor
The best places to get armor is to beat the campaign, collect skulls, or through online game play.
you get all the vidmaster achievements on halo 3 and halo 3 odst
NO