*cough-cough*
NBC suit. Razor would know that he would have a one-in-eight chance of going up against the Alien, and I don't see why he wouldn't be prepared for that possibility.
Its 1 in 16 as someone pointed out, so he probably wouldn't take it. lets say your playing a game, and you get to pick and equip one of two items, one gives +50 attack and defense against werewolves (with a 2% spawn chance) but -1 against everything else, while the other gives +1 against everything
While your fighting a werewolf you would argue that of course you have that item equiped, but i really doubt that you would.
Now, before you say he wouldn't have that sort of thing, keep in mind that this is a guy with a high intellect - he could probably make his own NBC suit that would work better than one he could buy.
If im not wrong, i think he's a mechanic, and makes awsome gadgets and cars and stuff, this seems like a bit of a different feild of study (but ill assume that he is able to buy or get a millitary grade NBC suit if he really wanted too). Also, in the time he has i doubt he would prioritize a 1/15 chance item.
Also, your argument for the suit slowing reaction time is invalid - most environment suits, especially NBC suits, are specifically designed to maximize the user's movement range while offering the required amount of protection.
Armor was designed to minimize weight and maximize protection, but a guy in leather armor is faster and is better able to react then a guy plate mail, and while platemail is better for combat, it is also slower.
And did you look at the wikipedia picture of the suit? It seems pretty bulky and cumbersome to me, yeah they have no problem shooting a gun or running, but it would be a serious disadvangage in melee, and perception as well.
the suit would mess with your: hearing, range of vision and your sence of smell, making it troublesome for anyone not needing it.
And again, the Alien's acid is meant for blinding, the likelihood that the alien would spit on Razor's chest first is extremely low. You also completely discount liquid dynamics - when the acid hits his goggles, there will be some splash, yes, but as the spit is designed specifically for blinding, the shape of the spitting organ would be optimized to maximize the amount of acid in the eyes and minimize acid that lands elsewhere.
If i got a anti tank missle weapon and i shot it at you, you would die even if it wasn't designed for anti-personal use. Likewise the acid WILL BURN THROUGH YOUR FACE (as metal>face and acid burns through metal). Also, the acid isn't really designed for blinding, its designed to eat through anything, which includes all your fleshy parts.
Spitting acid in your eyes will blind you by virtue of eating through your face and eyes, so i doubt the alien would have perfect pinpoint accuracy because its not needed.
And not very much acid needs to miss the goggles (and i think at least 50% would) you for it to burn through your face cause serious damage.
Another reason to wear the NBC suit is that it incorporates medium-strength armor - it's designed to keep soldiers safe from NBC threats while in active battle.
Armor is better in every aspect at being armor then a NBC suit. Also, does Razor (ever) wear armor? he fights alot, and knows he fights often, if he would wear it during the regular show i would agree that he would bring it with him, but he doesn't (ever?) wear armor.