Those ebay pens have done ok for me. The 532nm I have flickers but works while the 405 works perfectly. Build quality is well. Cheap as expected but for 5$ not much more is expected :) you can use a single lithium with a spacer but not 2 li-ions.
I've got some blitzlinears if you want :) you would be able to run your diode off of 1 li-ion too. It's stil 20% off LPF so if your interested PM me :)
Hey grainde thats an awesome photo gallery you've made there and an even awesome 520 colour :D
btw i have some diffraction gratings here ill gladly send you one just PM me your address :beer: this really looks more blue than green
edit: noticed you just got one lol if you want it anyways still...
This is an awesome + unique build :) With just the module alone you should be ok about 20 seconds. It's so compact though so it's fine but great job :D
+rep'd