For canister lights.. Yazid did qualify its meant for Tech divers. You do not just buy a canister light.. u gotta learn how to use one (drills with canister lights) and have the rest of the setup in tech specs. Else, you may end up tangle up the wire, hose and in an emergency.. may have problem getting out of your BCD. Not recommended if you are not trained to use it.
For a general purpose (primary) dive light, I'd recommend UK SL3. LED with 98 lumens, 3x C size batteries with enuf reserve juice for a few dive trips. Very robust construction.. DIR compliant and above all.. its relative cheap. You should be able to get one for abt $70 come with batteries too!
U cannot use this for video thou.. as in all DIR compliant lights.. they have a hot spot, good for cutting thru poor viz, signaling and pointing, but some may not like this.
Its may not be the brightest light underwater, but always 'above average' and is more than enuf for night dives. But these days, I seldom use it coz I usually dive very close to the bottom and the SL3 is too bright! I use my small LED light (30 lumens??) from my strobe while at bottom. Only use SL3 for signaling, during decent, accent and on surface.