I live in Minnesota...and do lots of bass and walleye fishing (a lot of times...at the same time!)...and no doubt...the 3.5" Swim shad on a swim jig with skirt....or w/o the skirt.
Rig the swim shad side-ward (side up) and use the same rig in the slop for bass. The wide profile of the bait on the weeds helps keep the jig from falling through the mat. Try it.... you be amazed how they blast it!
I like to use 1/4oz swim jigs for my "all around" swim jig. Heavier if your fishing deep or in heavy current.Unfortunately (or fortunately depending on how you look at it)...Northern Pike LOVE swim jigs too! Most of the time you can go without a wire leader....but be prepared to donate some to Mr. Pike.
If you want to catch LOTS of walleye...The 3" CCM Glider bounced on the bottom is a walleye killer. Does are darn good job on largemouth and smallmouth too!
By far ... my favorite swim jigs are yankem jigs...made by one of CToms neighbors in Rochester, MN.
The FatHead is my favorite because it's designed to slide across the top of the weeds when you are slop fishing...and does a great job of being a plain ole' swim jig. As soon as the jig gets to the edge of the weeds...let it drop. BAM! The bass (and Pike) will also blast it through the weeds and Lilly pads.
http://www.yankemjigs.com/AboutUs.htmlAndy