Jackfish is right. better to get the bigger and layer. If its warm and rainy, you can wear just ther raingear and not overheat.
Also, the dedicated raingear tends to be much more waterproof than the insulated stuff thats supposed to be waterproof.
I have Cabelas "dri plus" which is generic "gore tex" and it works great. My only complaint is the outer shell material which is a micro swede is not waterproof, it has a membrane inside it. This means the outer layer holds some water and drips long after the rain is done. But most hunting rain gear has this outer layer and all will probably suffer this problem, even the gore tex ones. Anyway, the waterproof membrane keeps the water off you and you stay dry.