Cant tell you how they compare but can tell you that I have a PowerVamp CoolSpool 29 (29 amp-hour rating) and it has been excellent. Available is a padded nylon carry case for those who wish to carry on. However, this mother weighs about 70 lbs even though it doesnt look like it should, so secure it well or perhaps a smaller CoolSpool unit will be adequate.
Bought mine at HeliExpo several years ago and purely by chance was able to deal directly with Richard Roller, President of PowerVamp. Only bought one but now he treats me like a long lost friend when I see him at HeliExpo each year. A pleasure to do business with and a genuine nice guy!
