2% is definitely "stronger" and more harsh. But a lot of people prefer it to the 1%.
The 1% is said to be about as effective in treating hairloss as the 2%.
More people may opt for the 1% because it's easier in some places to obtain. It's also less harsh and can be used every day.
If all you can get is the 2% - then by all means have at it.
Use the 2% 2 - 3 x weekly.