The pistol is more versatile, than the rocket launcher. If another spartan is charging you, the rocket does more damage, but its slow, less accurate, and there is a high chance you might take yourself out. The pistol is still very powerful, with a little practice can be used short range effectively. In which case you can use the 2x scope to gain a semi-sniper gameplay, or a running rioteer with only a pistol. I say Pistols.
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'Thanks for ripping off my friend. He has a magnum.' - SkogenJake
'I was like a 13 year old girl meeting a backstreet boy' - Ski@Jaypeak2 ... on meeting Glen Plake