Can this use digital servos without having a glitch problem, or a speed problem? If so, tell me the best servo to get for a good price for racing.

no issues here with Jr servo's. They are super reliable. jr9100s is the ticket.

Using an M11 here with digital servos, the only issue I'[ve ever noticed is the steering acted like it had a "stutter" to it when I was moving it back and forth on the bench. The cure here was to go into the setup menu and put the radio into two channel mode instead of four channel mode,then the stutter completely went away.

Something to keep in mind if your steering looks a bit weird.