Newbie looking for a green laser

[jzmtl]

Newbie in laser so excuse any stupid questions.

I'm looking at the green lasers on DX, from 5 mw up to 30mw all seem to have similar price for under $20. I'm basically looking for one to use for PP presentations (in relatively bright room, only light directly above projection screen will be turned off), and pointing out things outdoor.

What is the max power I can go without any danger from IR etc? I noticed red is actully not bright enough to be seen easily in relatively well lit room and slides with colorful pics, so I want something that's easily seen. Outdoor will be mostly around city, so light contamination is quite strong.

Also not sure if this is a silly question, but what kind of runtime can I expect if I were to use 2xaaa eneloop?

Edit: I noticed in some reviews say certain ones will dim down after a few seconds of on time, obviously can't have that.

 

[gorn]

At the task force I worked for we used 5mw greens for instruction. We has some higher powered ones but they were way to bright to be practical.

 

[Kenom]

Anything above 5mw green in a presentation is going to be OVERKILL.

 

[jzmtl]

Looks like I'm going with 5 mw. I suppose I can always get the higher powered ones later since they are cheap nowdays.

 

[luvlasers]

I vote for 5mW too as the best power for presentations

In a large room where the audience is not sitting near the screen/board I'd go for 10mW but for normal sized rooms with a close audience, definitely 5mW.