In San Diego, it rains so infrequently that it's not worth my effort to buy serious rain gear. A few days a year I just ride a little slower (to minimize spray from unfendered wheels) and generally get wet. If I lived somewhere else, I would spend the $$ for proper kit, but I can deal with what San Diego can dish out.

People at work think I'm crazy, but I just tell them I have the superpower of being completely waterproof. Any amount of rain can fall on me, and I won't be harmed in the slightest.

Of course, it helps to have a shower and a locker and a towel at work. (and of course at home)