weblogic clustering or F5 LTM?

Hi All, I am new to weblogic and F5 LTMs.We are designing an Infra Model to host one of our applications. Below is our architecture model F5(1600)->Oracle i planet web server->LB->WebLogic App server->DB tier We have finalised F5 at top,but need sort the LB between web and App tier. Checking options like to use F5 between web and app tier.Also got to know that we can make use webLogic clustering to do LBing between Web and App tiers. Need help in chooding.Any hint/help is much appreciated