Ive used lots of different stuff for bugs, some commerical, some not...i think the only thing that works for sure though is any product containing DEET. i try to purchase the spray kind with the highest DEET concentrations---they vary a lot from brand to brand, so look at the ingredients. i dont think the brand is that big of a concern, just as long as it has a lot of DEET in it. several studies have been conducted on bug repelents, i think most have come up with the same conclusion.
Ive also used clothing treated with permethrin, which can be found in a spray you treat your clothes with and let stand for 24 hours, or a bottle you wash your clothes in and let dry. if works, but over periods of time it wears off. i am also not sure about its side effects from prolonged use, the stuff is pretty toxic so id be careful with it (despite what anyone says) and use it sparingly on hats or anything that comes in close contact with your skin. as far as clothing that is suppose to repel bugs...im not sure. it might just be treated with permethrin also, so it would wear off in time. might be better just to spend less and buy the permthrin and treat your own clothes. a 6 ounce spray bottle usually is enough to treat about 2 sets of clothing, depending on how thick you lay it on. this stuff is especially good for repelling ticks, it keeps them from hiding in your clothes, especially if you apply it heavily along seams and other areas they can hide in.
other than that adequate clothing is the best bet to help keep the bugs off you. now days with the threat of West Nile and other diseases carried by biting insects it pays to cover yourself. i usually wear a hat and a long sleeve shirt when i fish, and sometimes even a head net depending on how bad the bugs are. lightweight, quick drying long sleeve shirts are a usual part of my fishing attire, they not only protect you from bugs but also the sun---which is important if you spend alot of time on the water like a lot of guys on this site do.
I found this site with info on permethrin. im not sure about all it says though, as the stuff ive used says on its label it is toxic and should not be applied directly to skin.