3W is more than enough! I regularly use 1W and often into very inefficient antennas (shortened verticals, small loops, etc).

That seems to be fine on 80m for contacts out to about 500km, and on 20m I can reach the West Coast of North America from the East Coast, as well as South America with no troubles when the geomagnetic storms aren't too bad on 40/80, and when the flux numbers aren't causing bad QSB on 20.

I'm used to low signal reports (339 etc).

Trans-Atlantic contacts with 1W and inefficient antenna for me happens but infrequently, and often after several tries.

Now 1W with a more efficient antenna, for example a 1/2-wave or more dipole on 80m/40m or a 1/2-wave or longer vertical on 20m over salt water, or something like a vertical moxon, phased verticals, beam, etc. now that's a different story, now the 1W will be a little easier to make those Trans-Atlantic contacts, and on 40/80 your sig reports are going to be more like 559 than 339.

I have yet (at 1W) to make any trans-atlantic contacts on 40m though many others have.

The advice to add /QRP to your callsign, or just adding it to your CQ is good advice.

73!
Martin.
VA3SIE.


Link:  ChilliCon 2007