there is no ingrown hair when using electric shaver.
after using it for few weeks, i think electric shaver is less efficient when compared to manual razor.

electric shaver take more time to shave. u have to round back to shave the same place to get the same feel as using manual razor.
its like 3 minute with electric shaver, manual just 1 minute and done.

but it does eliminate the need to keep on changing razors every week or days.
btw, electric shaver have better feel, eg less prickly feel.