I use a vinyl clear rain jacket for when its really raining (like the $9.99 jacket listed on Performance). This keeps me warm and some what dry in bad weather and is cheap. If the weather is warm (60-65F+) or only lightly raining I do without and just get wet. For me I am more comfortable wet from rain than wet from sweat. I'm sure the ShowerPass jacket is much more comfortable but I don't ride in heavy rains enough to warrant to much greater expense. I will probably only ride a dozen commutes in weather sufficient to drench. I use weather.com to find openings in the rain showers so i can avoid the worst of the weather. This is in fairly wet Cleveland. I'm guessing areas like the NW have alot more days of all day rain where an expensive jacket makes more sense. For me I spent the extra money on a softshell winter jacket that keeps me warm below feezing and is mostly waterproof for those rainy winter days.
Craig