I purchased a Voltaic Systems "Fuse 6W" 6.0W Portable Solar Tablet Charger about a year ago in preparation for a Northern Tier trip this year. I strap it on the top of the gear on my rear rack and it has a full charge in a couple of hours. It seem fairly rugged and I've had no issue with it. I use it with an Android device but the description says it's compatible with iPhone and iPad.
Comparing the specs on both systems, the Venture 30 has 7800 mah compared to the Fuse's 4000 mah (so it makes sense that the charge time would be about half) the panels compare at Nomad7 (7w) Fuse (6W) so the systems are roughly the same except that the Venture 30 has greater capacity and it's separate from the panels, so you can use it without the panels. since both systems are similarly priced, that puts the Goal Zero as a better buy, based solely on the numbers.
You can also get bigger panels from Goal Zero. there's a 15W, and a 20W that are compatible with the Venture30, and you can link multiple panels together (not sure if that's practical on a bike, but maybe, if you're taking a rest day on a tour) They also have larger batteries. Also you can buy all the components separately from them too, and I recommend going for more if you can afford it and you'll be semi-counting on it. go right for a sherpa50 with a Nomad 20... it's pretty pricey though. you can link multiple Nomad7 together, but you're still limited by the 7 watts max which is OK for charging a smartphone and the Venture 30 together, but not also, a light, a BT headset all at once
The Fuse you can get an additional external battery for as well
Also, now that I examined some of their other options it looks like they have some other offerings that might be worth looking at that have separate batteries although it doesn't look like the panels are hinged, which could be less efficient on a bike (the nomad 7's are 3+ hinged panels, a I can have one on top, one facing left, one right, to better ensure that at least one or two of them is facing the sun as I ride)
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