If the ESCs are cheap I'd advise adding some protection, perhaps a 2k2 resistor
in series with the logic signal. I had one explode (cheap from eBay), so I don't trust
them very much!
The Servo library can drive any pin and upto 12 servos/ESCs on the Uno. It does
take over timer1 though, so you can't use PWM on pins 9 and 10, or the Timer1
library.