it's not slow in my browser.
But I can't destroy no one of big ships... I did not like what I have to constantly press and press Ctrl on each shot. I want to press and hold the key to weapons firing. If the bullets for the weapons are infinite, then it is better not ask to press a button - even shoot at all times.
It is bad that there was not a rocket ...
I liked the "eat" a UFO when I took them to ram - there were no explosions, and my life have come far in the negative.