Originally posted by Quartermaster James I have found no difference between the Wasabi batteries and the Pentax in my usage. Worth noting however: the aftermarket chargers that come with the Wasabi batteries are quick chargers. Use them only when you really need to sacrifice longevity for recharge time.
Agreed.
If you're worried about compatibility, always charge with the official charger. My Pentax charger that came with my K-3 charges batteries up to 7.6 volts, but the generic charger that came with my batteries charges it to 8.4V. This might be for quicker charges or to squeeze a little extra battery life, but if you stick with the official charger you won't exceed the manufacture intended voltage (though I haven't had any issues either way).
In all my time buying aftermarket batteries I always check reviews and buy the popular ones that have sold well. I haven't noticed any significant difference, and some even last longer than the OEM batteries. Even if there is a slight drop in battery life, at less than half the cost you can still beat the total time of an OEM battery. Currently I use DSTE batteries which is the best deal I could find and they work as well as Wasabi's I've used in the past (
--link--).
I like having at least two spares in the field as well. When I have to change the battery I get a reminder of how much I have left so I can estimate if I need to slow down or can keep shooting at the same rate, and when I have to put in my last battery I know if I need to be more frugal.