Rev counter, yes or no

[helijohn]

Should I or not?

Turnigy Multi-Blade Micro Tachometer EDF Heli aero prop | eBay

[Gixxer]

It's a gadget... of course you should

[waveydavey]

An even better gadget is the magic eye tacho from Turnigy, an awesome bit of kit

Turnigy LCD Tachometer for Helicopter 800~4200RPM

[Vikki]

Spouse looking: no.
Spouse not looking: grab with both hands and run.

[helijohn]

An even better gadget is the magic eye tacho from Turnigy, an awesome bit of kit

Turnigy LCD Tachometer for Helicopter 800~4200RPM

That one looks nice but you have to hold to the eye like a camera and isn't that gonna be hard while having a Tx in both hands.

I got one of another type but you have to stick reflective tape to everything.