4S probably no but 5s and 6S yes.

Paul,

Are you using the one with the anti-spark button or just the straight plug?  In the photos posted here of your Predator I can see the arming plug on the bottom of the airplane with a button behind it.  I didn't know if that was the anti-spark button or the motor start button.

Thanks,

Shawn

This may already have been talked to, but why is there a need for an anti-spark device?  Is damage being done to some or all of the different electrical devices in an electric power system?  I am serious, I really want to understand this problem and know when I need to take precautions.
Andy

Castle Creations calls the spark "a friend ".
 I haven't used an anti-spark device on 4S and 5S stunters. My 2M R/C pattern ships use two 5S 5300(10S), and no anti-spark device. On the 10S setup, I use 10 gauge  wire and 5mm bullets. I periodically swipe the male bullets with a piece of 400 sandpaper . Seems to work.

As I understand the concept the anti-spark device is not really a spark suppressor, more like a spark preventer.  A resistor routs the +V to the ESC through a pushbutton switch to pre-charge in input decoupling capacitors prior to applying the full voltage from the battery.  The resistor essentially drops the voltage of the battery to give the ESC what would be a battery of a lessor cell count.  When the switch is released and the ESC is connected to the battery, the full battery is not looking at a dead short because the input caps are already charged up.  It's simple and I guess it works but the resistor would have to be sized to the battery you plan to use.  Or maybe they just size it to work with a ten cell battery and everything below just works.  I have never had a problem with my setups because I never run more than four cells. 
Andy

As I understand the concept the anti-spark device is not really a spark suppressor, more like a spark preventer.  A resistor routs the +V to the ESC through a pushbutton switch to pre-charge in input decoupling capacitors prior to applying the full voltage from the battery.  The resistor essentially drops the voltage of the battery to give the ESC what would be a battery of a lessor cell count.  When the switch is released and the ESC is connected to the battery, the full battery is not looking at a dead short because the input caps are already charged up.  It's simple and I guess it works but the resistor would have to be sized to the battery you plan to use.  Or maybe they just size it to work with a ten cell battery and everything below just works.  I have never had a problem with my setups because I never run more than four cells. 
Andy

Thanks for the explanation. One day I'd like to convert to electrons... Learning everything beforehand.

I found this info on how to size the resistor to your ESC. Hope it helps.

http://rc.runryder.com/helicopter/t547501p1/

Douglas and any others.

It appears that, if you use the formula that is presented in the link you posted, you will come out with a resistance that is too high for proper spark abatement and ESC arming. Read all of the comments it the thread. I think Igor Burger suggested a 10 ohm resister which is way different from a 1500 ohm one.

Igor can correct me if I am wrong.

The thread in the link stated an EXAMPLE to demonstrate the formula.

Did you do the math in regards to your ESC & Battery pack?

Does one size fit all (10 Ohm) or can the resistor be better matched?

If I paid $400+ for a complete elec. system & charger,
I'd be a little aggravated at having to change terminals due to arcing.

Does one size fit all (10 Ohm) or can the resistor be better matched?

As I recall (I'm too lazy to do a search), the resistor value has to be low enough for the voltage at the ESC to get close to the battery voltage before the ESC measures the voltage to set the cell count.  I'd guess the value would depend on the ESC and how much freedom the designers were given to program clever things into it.  Also, as I recall, Castle's response to the question of how big a resistor to use with theirs was not to use the automatic cell count feature.  The result of the discussion was that I decided not to use a desparking resistor.  I'll just change the connectors from time to time.  I have found that by first making contact with the + side of the Deans arming plug, then firmly rotating the - side into the socket, I can usually avoid the plug sticking partway in.

On another subject, if you calculate the power requirement for the resistor using "Twinkle, twinkle little star, power = I squared R, you get about 40 watts for a 5S battery and a 10-ohm resistor.  That's what you'd use for continuous current, but I'd guess we'd only need 1/2 watt or so.  Assuming the resistor either has 10 ohms or is an open circuit, a resistor failure due to picking too low a power rating would be benign.  What power rating do folks use?

It might be critical.  That's the problem.