[i love you]

It depends on rather you are used to pressing your keys all the way down or not. If you are one of those players who does not like pressing your keys all the way down, get an o-ring. If you have a black or red switch and you do not like the fact that it is sometimes hard to tell if you pressed a key or not, get an o-ring. If you have a blue or brown switch and you do not like the loud noise, get an o-ring.

Otherwise, I would not recommend it at all.

As for gaining speed...I will get back to you on that.