4 strokes are fine pretty much everyone here uses them and 2 strokes dont have the tourqe a 4 stroke does. i like the 2 stroke smell lol but i have no use for a 2 stroke not enough toruqe for me.
2 strokes generally wind out faster, and higher, and have more HP for their size than 4 strokes. 2 strokes can have just as much torque as a 4 stroke, but often dont have as much bottom end torque, the powerband on a 4 stroke is normally pretty equal throughout the rpm compared to a 2 stroke, where it depends a lot on the tuning, and pipe. Theres nothing wrong with a 2 stroke and for the most part they have plenty of torque for a kart, and you can easily get more torque by getting a tuned pipe which focuses on bottom end more than top.
Also, with a performance 2 stroke pre-mix engine you really cant put around on it, you have to ride it fairly hard so you dont foul plugs, if its oil injected, you dont have to worry as much about that.