Find yourself a Costco up there...they have S0-3, RE730's, RE950's, BFG K series, and Michelin Pilot series. Remember you get what you pay for!
As for Toyo FZ-4's Ive had two sets and both lasted 2 years easy. I had a 2.5 inch drop and -1.50 and -1.75 degrees of negative camber. I only had a problem with this last set because my struts were blown and it caused irregular wear on the shoulder, which no tire would be able to take.
And for Prowler look how much tread you still had on the outside of the tire. Two months without a proper alignment would kill most any tire. Remember tires aren't designed to ride on just one shoulder. True they suck beans in the snow, and the rain if it was heavy also took a toll on the handling. The reason the SO-3's are so good is because they have really wide circumferential grooves to store the water for the split second you are over it. Whereas the FZ-4's only have two grooves and try to evacuate water from the sides, which takes considerably longer to do, and is easily overcome by deep water. The 730's have a similar tread pattern and the problems would be similar in deep water. Tread depth is your best friend in water.