Rayman-I have been testing and using a Scorpion LiPo pack. I have been charging at 5 amps. It takes 1.5 hours to complete a charge at this rate. It can be charged up to 9 amps. 90 % of capacity is reached in 20-30 minutes, then the charger goes into a slower constant voltage charge to prevent a destructive overcharge.
The pack has very good Voltage 7.20 volts average over the entire discharge (7.25 V average after I shortened the leads, had to add new shrink wrap). It has very good punch and top speed in a stock touring car. If you delay running a charged pack the voltage is quite a bit less. .4 volts less after 15 minutes in my test, so its important to time the charge to finish at the time you want to run it for racing. I think you could race this pack when the rules allow it, but not with two packs at the club level due to the slow charging. You might need three, and several chargers as well. You can run it before it finishes the charge, but it will be at a slightly lower voltage.
I noticed that one company sells a charging "bunker" to charge this type of pack. If you use the proper type of LiPo charger like the scorpion charger you should have no trouble, but it is still reccomended that you put the pack on a non flamable surface. I use a wide mouth ceramic coffe mug that I call my "mortar tube". No incidents to report.
This pack is rated to 60A continuous ( higher peak) and is limited by the wiring according to the manufacturer. The stock wiring is a long piece of 12 gauge going out of a Deans connector.
There is no excessive comm wear. The comm looked great.
It is no problem at all quiting when the car slows as it is easy to tell. I removed the low voltage cutoff the pack came with. Way too many connections to make one run for me.
I have some more details and pictures of my pack and reshrinking on another thread on this site. Some discussions and photos are near the bottom of page one when set to 40 topics per page.
Losi Constant Velocity Drive (LCD) vs MIP CVD