Mr.E wrote:

"Good" "plastic" any recommended brands?

Look for 'tactical' flashlights in the gun and police web stores.
Streamlite is a good, well known brand. I don't think they are
'plastic', but more of a composite material (not sacrificing strength,
but decreases weight).

Get one with multiple functions, like a
key-chain/Kubotan/stun-gun/stun-flash for example.
If you plan to carry it all the time, that is.

Follow the manufacturer's recommendation for batteries. A great
flashlight is a luxury item that you can expect to pay upwards of $150
for.