The 1.8W 445 I have, I built using a host purchased from from a member here (Mrcrouse), and a diode module/driver purchased over to
DTR's Laser Shop. I purchased the one titled, "1.7W 445nm Copper Blue Laser Module W/X-Drive & Three Element Glass Lens" for $89, and it metered slightly over spec (bonus!). Then all I needed was to put it all together and buy batteries.
If you want a decent build that is ready made, they
HERE or
HERE
Both are reputable builds. The first one is the same as the first laser I bought, only in a different host color (purchased mine from yobresal). The second I have not had any hands on with, but Blord builds/sells some sweet lasers (and hosts), and he is well trusted here.
Good rule of thumb...
1W will burn VERY well up close, but may have a somewhat limited range (depends on how steady it is held). As you get closer to 2 Watts or above, the more range you will get. However, it is important to point out that some of the higher power builds use a lens called a "G-2", to add to the output power. These have a shortened focus range, which means a larger spot as you get further from the laser.
Builds that have the higher power while still using the standard three element glass lens (or similar) will have a better looking beam and spot, while giving you a sweet burning experience too...
Last but not least, take some time and do some reading around the forums. Many around here very frustrated answering the same questions that have been already answered a few hundred times throughout the forum.
You can PM me if you need more direction.