150mw is not to powerful either for a first laser. As long as someone is responsible with it.
Or in fact any newbie that comes here?
Shouldn't we all be recommending 5mw 6$ ebay lasers as the 1st toy?
They are still alot of fun, and you can get a feel for what better NOT to do
without putting yourself and others at risk.
If you still like lasers and want more, then by all means do.
But please, people, get your feet wet with low powered lasers, not class 3 or 4 OK?