On the cheap, I'd go with Frogg Toggs. Just buy them a size larger than you think you wear. That also helps when you use them over Winter clothing.
I have a Walls Chiller Killer snowmobile suit that I wear for cold weather fishing. I was busting across the lake, several years ago, in mid 30deg weather ... and the wind was coming right through the snowmobile suit. I put on my Frogg Toggs, over the suit ... and stayed toasty warm for the rest of the run.
I've fished in rain & sleet with my FT's on, and stayed dry and warm (and not gotten sweaty, like with PVC suits). At around $20 per piece (jacket/pants) I can afford to replace any piece that gets worn out.
Can't help you on experience with any of the "high dollar" rain suits.
... cp