A gas generator is a very good option for emergency short term outages, but there are many downfalls to this route that may affect different people with different uses in a few different ways.

Gas Can

Gas Generators

Monitoring

Require fuel monitoring and refueling which could mean you need to transport your fuel with you or have a fuel replenishment plan in place.

Maintenance

Require regular maintenance, with any motor there will always be much need routine maintenance.

Operating Cost

Have a fairly substantial operating cost if used for any long duration of time with Gas/Maintenance fees.

Burn Rate

Depending on size of generator are either on or off, even if your connected load is only a 60watt lightbulb, your generator is essentially wasting that excess production via burning the precious gas reserve.

Noise Level

Are loud and noisy, depending on your intended use you may not want to hear the noise of a generator.
Sun

Skytek’s Gen2k

Monitoring

Requires no fuel reserves to operate on a daily basis.

Maintenance

Does not require a maintenance program or routine.

Operating Cost

Zero operating cost involved.

Burn Rate

Being that this is basically a smaller portable solar system, it works in the same way that you store your power and use that stored power on demand when the associated load is running that is all of the power being consumed from your reserves.

Noise Level

Operates with a noise level Quieter than a whisper.