Don't really consider nitro an upgrade. I can't think of a thing that is gained by it. The problems with nitro:
1. Crawling is an "upclose" type of thing, unlike running nitro on your MT or car. When you are running a nitro on the track you don't really get any closer than about 10 feet or so, crawling you rarely get 5 feet away from your truck. You'll get brain damage from suching all of those nitro fumes and noise.
2. Nitro uses unspent fuel as a lubricant for the engine, that unspent fuel gets pissed out of the tail pipe, ergo, on to the rocks; I'd be pissed if I was next in line...
3. Nitros torque-band is at very high RPM, which means you'll have to run the engine constantly above 80%. You'll get about five or six runs (max 10) before a rebuild was required.
4. You still need batteries.
One possible solution would be to run a 4-cycle engine, they produce a lot of torque and a lot lower RPM, but they are a lot heavier...
Stay electric: charge, plug in, turn on and crawl... "thumbsup"