I bought some 7.2V Powerizer batteries for my TT-01 basher a few years ago, and they worked just fine. I bought the 3000mah packs that were their top of the line back then, and the packs still hold a full charge today after 50-100 charges each. I wouldn't ever trust the Powerizer packs in my Pro4 that I use for racing, but from my experience they are solid packs considering the price. I would imagine Powerizer's other products are of similar quality.