It depends on which record you mean. Most believe that the world record LMB was an intergrade ( cross like an F-1) but know one is sure. Most of the more recent large LMB are Florida strain females. Recall a recent post where I pointed out the fisheries scientists tell us that while fla females are big fla males are small (when compared to northern males). The population is half male and female. The question is what do you want. A few big females and lots of small males or a smaller but more balanced sized population of northerns , F-1s and a couple of flas. This of course is dependant on your location and how each strain will do there. Fla LMB up north don't work well if at all and northerns in south Fla likewise.