I've had problems with poor quality corallys - missed my first regional win because of them
they heated up because of the poor connection (brand new too!) and desoldered.
You can read my experiences with Lipo in the trakpower review on here - pretty similar really. In the touring car it was a DREAM - really no messing about, recharge after racing and that's it.. loads of power, like the very best team cells + a bit more!
First time in the buggy I found it a handful tbh - but I hadn't adapted my setup - slower motor / lead weights. Since then I've raced the Tamiya Durga with an entire strip of lead next to the trakpower and the car has been awesome and no different to drive from nimh cells, apart from feeling like I had some awesome cells in the car. Come off racing, bang it on charge & back out to marshall.
The only problem I've had was when I left the trakpower in vickys car for two weeks. The large capacitor on the Novak ESC totally drained and ruined the pack - my fault but it just shows you need to take care.