I've fished the lake for at least a week every year since 2000. St Clair is over-rated. Not sure why you would want to go there. Season doesn't open until June, so May won't be an option for you. I would also wait until the first couple weeks of the season have passed before you go. Fish with someone that is licensed to guide in Canadian water...not sure how that works though. We got 5, 50"+ in my boat for our week this year. Our best in a week is 7 over 50", but it definitely isn't as easy as some people think. I know quite a few people who have gotten their butts handed to them up there. A good guide will have you on fish though. Have fun. Get a 50" on a fly.