which type of sand tire is better for recreational duneing? "V" blade or "Straight"

also, my 400 4x4 scram has the 23f/22r combo stock from the factory..... can i run a 21f/20r combo?

front tires, are the sand tires worth the money? or would it be better to just leave a stock knobby?

 

THE V BLADE WOULD BE THE BEST FOR REC RIDING,AND THE STRAIGHT BLADE WORKS BEST FOR HILL RACING,WITH THE V BLADES YOU CAN RUN STOCK FRONTS. NOW IF YOU HAD STRAIGHT BLADE IT WOULD BE WORTH THE MONEY TO BUY SAND TIRES FOR THE FRONT,BECUSE THE STRAIGHT BLADE WILL PUSH THE STOCK FRONT TIRES AND ONLY PLOW SAND.WHEN FRONT SAND TIRES WILL CARVE AND TURN REAL NICE!