I run a red top 25 in the 106 and it's genuinely awesome. Went weeks without being touched (like 3 months) and starts on the button as if it was just charged.
When it eventually dies (it's about 3 years old now), I'll replace it with a lithium ion one like Josh's - even smaller, even lighter, and more powerful. Oh, and cheaper too. Absolutely no drawbacks as far as I can see, unless you're running a large stereo or something, in which case battery weight isn't your problem
