The only issue you may have with the 1W is that they will be able to send to nodes that will probably not be able to contact you back. Because they are lower power.
So while you may be able to send really well, receiving may be a bit more difficult.
Ive heard of people saying that the 1W will muddy up the radio space since its basically one node "screaming" over others. Im not 100% buying it as 1W is still pretty quiet compared to other electronics in other spectrum. But thought I would mention it.