Not sure how big your track is, but thirty minutes just seems iffy in a truggy unless you have huge brick of a pack. It is iffy in a buggy, so I know a truggy is going to be damn near impossible if the track is medium to large sized.

I would just plan for a battery swap at 15 minutes. If your pitman swaps fast, you shouldn't lose too much time to the nitros if you only take one pit stop for the swap. It should be pretty even to their multiple pit stops. I finished fourth or fifth in a 30 minute A-Main out of 12 guys a couple of weeks ago and I had to run out of the stand and do my own battery swap since the nitro guys were afraid of a little electricity, so it can't be that big of a disadvantage.

The math above doesn't lie. A buggy is going to run at 190-220mah a minute during a race. I have been tracking my run time religiously the past couple of weeks. Truggies take more mah/minute. My buggy would need at least a 5s 6000 assuming 200mah per minute and no practice laps to make 30 minutes. Truggies run close to 250 mah/minute realistically which means a truggy would need at least a 5s 7500 for 30 minutes. Assume bumping to 6s makes you more efficient and you burn 225/minute you still need a 6s 6750 for 30 minutes. Say you really feather the throttle and gear it fairly slow and you get buggy efficiency of 200/mah a minute you still need a 6s 6000 pack.

Mah/Minute * Desired Runtime = Pack Mah.