I used a slip float this year when I wanted to fish deeper 8-10 foot water and couldn't use a fixed float. Worked ok but missed more bites than normal. Was using JDM rods with the tiny guides and could feel the stop knot tic the guides while casting and knot going through the guides affected the casting distance. Rods with bigger guides like your St.Croix rods should have no problem. Next time I'll try it with my 7' Loomis.