I don't know if this is possible in a limited space.
If I chose to write an equipment review on a sea kayak, it would be stupid, because I don’t know much about them. If I chose to write a review on a Formula One race car, it would be worse, because I really don’t know much about them. I guess other people just like to write reviews, even if they don’t carry good information.
In most of these outdoor/solar battery systems, there are two or three main components. One is the silicon solar panel which captures the sunlight and produces the electricity. In some cases, this feeds into a storage battery to keep it charged up. In a few cases, there is a regulated power supply that runs off the battery and supplies regulated voltages to the load device that you plug in.
If you are running one of these things for the first day, you are mostly running on the power stored within the battery, and the solar panel doesn’t have too much to do with it. Little by little, the solar panel will generate enough power to try to keep up with the battery demand. And the battery demand relates to the load device, self-discharge of the battery, and regulator efficiency. In other words, you could have a great solar panel, but if the battery system is funky, the load device doesn’t get charged very well. Equally, you could have a funky solar panel that can’t keep up with the battery demand, so the load device doesn’t get charged very well that way, either. My point is that you want to separate the various parts of a solar system like this so that you know what you are getting for those ounces and pounds that you are carrying.
Frankly, you don’t know anything about the output wattage of the solar panel part. The manufacturer doesn’t quote it either. If you don’t know whether that wattage is one watt or ten watts, then you really don’t know how this thing is going to work over the course of a couple of weeks. If you just charge one load device on one day, you are mostly just sucking power out of the battery, so the solar panel is mostly a waste of weight and money. You want to find out whether it takes one hour for the solar panel to completely recharge the depleted battery, or whether it takes twenty hours. That means a lot.
If you make statements about how fast your load device was recharged, then you ought to state roughly the geographical location. If Nick runs his system in Palm Springs and reports the results, the guy in Portland is not going to be able to get the same results. If Nick runs his system in Palm Springs in July and reports results, even his neighbor is not going to get the same results in January.
When I ran my first system near San Jose, I measured the solar panel output, and I got a maximum of about 95% of the solar power rating that the manufacturer quoted, and that was only during the peak sunlight of the day. At other times of full sun, I was getting only 30% or so of the rating. That’s just the way that solar panels are. You can’t expect to get 100% of the rated maximum for all of the sunny hours of the day.
So, I recommend for the user to get a solar system that has a rated solar panel output that is at least double or triple what the load device consumption will be. Even more is better, to provide some protection against cloudy days, like Portland. If the manufacturer does not quote the spec for the solar panel, then one of a few things is possible. It might be a poor rating, so they are trying to hide it. That is where a proper equipment reviewer could be helpful, by furnishing real numbers.
Most of the time, a single crystalline solar panel is built with a rigid frame to protect it. An amorphous solar panel can be much more flexible, but its efficiency tends to be lower than single crystal. I think (believe) that this also has an effect on long-term longevity. If the transparent glaze over the solar panel isn't exactly right, it will have lost some of its transparency over a short period of time. Or, if the glaze isn't hard enough, it may degrade from blowing sand.
Like others point out, you want to go through all of the numbers and weights to see if it really makes good sense for you to purchase and use, so you want to think about the duration of your trips.