Tube vs. Tele

Ok so I am getting the 400L/5.6 and i was wondering which i would need more, a tube set or a 1.4x extender? I will be taking pictures of mostly birds. Right now I am leaning towards getting the tele but i thought i should get some second opinions. (I will eventually get both)

Thanks,
BB

I would get the 1.4 Extender, tubes will only help you focus on things closer too you, and that ain't usually birds. I use a Sigma 150-500 and 500 is short sometimes so I add the extender to take me to 700. your proposed 400 plus the 1.4 is going to give you 560mm

Welcome to the forum BirdBoy. Glad you will get the 400/5.6, it is a great "starter" lens for birding but I am suprized that you did not do your research before choosing it, like what does an ext. tube do vs. a TC and how do both act on that lens.