Camera a cobalt mine fragile thing prone to all sorts of harmful influences. If you want it served for a long time, then pay attention to the mechanical structure. If the shell metal, then at least not crack if dropped. There are models designed to operate in extreme conditions. Traditionally Pentax pays great attention to protect their equipment from the adverse effects of the environment.
A few years ago mobile phones used Nickel-Cadmium batteries that had a "memory" so to speak. What this means is that if you let you battery get to 50% of charge capacity and then charged it it would start to think that at 50% capacity it was totally empty. Many of us remember how quickly cell phone batteries seemed to die with the (Ni-Cad) battery. If you have a Nickel-Cadmium or a Nickel-Metal Hydride battery, make sure you let it run all the way down before charging to give it the correct memory parameters. Lithium mines Ontario Ion batteries have no "memory effect" whatsoever. This means you can charge your phone when the battery is at 80% or when it is completely dead without harming the battery.
Toshiba laptop batteries are excellent for this. They make it easy to have a spare battery for a laptop for many reasons. One is that they make batteries with high capacity. They are lithium-ion batteries. A Li-ion battery lasts longer than other batteries do. Because of that, they have a longer use life as well as not having to be replaced as often.
If you can avoid carrying too much water, you'll enjoy a far lighter pack. Your ability to find safe water and know how and when to treat it is a valuable skill. Pathogens can sometimes be found in water that seems safe. Much of the water we find outdoors is safe, especially at high elevations and when you're near the original source. Always consider what is upstream, and err on the side of caution if you don't know what is above you. Does the water Lithium battery stocks look clear? Don't worry too much about small animal life in the water. Worry more if there isn't any life in the water, and ask why.
You have more power to perform work better and faster such as drilling and screwing than the smaller model. Once I used the 18v model I found that I prefer to use it more often because it gives me more power to complete the same task with less effort. At the end of the day it is better and faster, productivity counts.
Another benefit of the lithium-ion Toshiba laptop battery is that it doesn't have any memory. This refers to an effect that many rechargeable batteries have. Each time they are charged and drained, they "remember" how far that charging goes, and how far down they are drained. If the battery doesn't get fully drained every time it gets used, it starts charging only to that level. For example, if it only gets drained 90% each time it gets used, after some time it only charges to 90%. Eventually, the effective use life of the battery gets down to the point that it can't be used without being constantly hooked into a charger. But li-ion laptop batteries don't have that problem. They do not need to be fully drained to be recharged and they will always empty and charge to their full extent.