I go with armor, for peace of mind. I prefer to make every shot count, so I prefer to be able to stand a bit of punishment whilst lining up a perfect headshot (or crotchshot, if I'm in the mood to). It just suits my style of play better. Even if I have an awesome weapon able to obliterate my enemies in one shot, if I have poor armor I tend to panic and miss in a firefight. Obviously this only really applies to fps (I had fallout 3 in mind whilst typing this), but as a general rule I tend to put armor before weaponry, usually ending up with the best armor for whatever particular stage in the game I'm at, and a moderately damaging, simple weapon, which suits me just fine... of course, I wouldn't say no to both