Reliability-wise, both CPUs will easily outlive their batteries' useful life at which point it is almost cheaper to replace the whole laptop than just the battery so I would not worry about it much.

For performance/watt and battery life, the i5 will likely lead if both systems have similarly sized batteries and similar drain/efficiency for all other non-CPU components. With that many ifs, things can swing either way.

If you plan to play 3D games, the A10 has a much better IGP than i5 so unless the i5 has a discrete GPU, you would likely be better off with the A10 in that case.