To Top Or Not To Top...That is the Question

Hey everyone!

I am currently working on my first grow. I've done a lot of research and my plant looks great as of right now.

Here is my question:

I have a rather small (area wise) grow room about 2ft by 2ft. I do have a lot of veritcal space however (around 5ft for the plant to grow). I am growing a 90% sativa dominant strain, La Lybella a new strain from Dutch Passion.

I currently am only doing one plant. My question regards topping. Because of the small area will topping this plant, creating two colas cause this plant to overgrow its room? I am running a 250W switchable MH/HPS Light. If I don't top, will this light not penetrate enough to satisfy the plants needs?

My plant is around 2 and a half weeks old and the 5th node is coming out now so I should probably do this quite soon if I do.

Suggestions comments?

Thanks guys!

i say top for 2 cola, a 90% sativa is going to grow very tall, if you cut it for 2 you'll get less height and more light penetrating lower throughout the plant to help for some more buds. thats my opinion