With 4.5 WPG things will grow fast, but with that much light things will quickly go south as well if you dont keep on top of everything, id say definatly go with the 65 watts for the moment until you get a feel for things.
Get your co2 setup correctly, get your water parameters correct, get your fertililiseing regime in place, its a definate learning curve in the beginning, its a bit of a balanceing act until your tank matures after a while, and once your comfitable with all of those aspects and your tank is up and running and problem free, then i would consider after a 2 or 3 month period running the other light and upping the wattage, but i think in the beginning to give yourself a good chance of success without many problems, id leave the F1 lighting until you have more experience and a good feel for whats happening in your tank.
Things will grow a little bit slower but thats ok in the beginning, thats what you want, you dont want things getting out of control to quickly.
Im running 3 watts per gallon and for me at the stage im at (only a novice as well) its more than enough for me to handle right now until i get more of a feel for whats going on.
Best of luck with it.