10 Watt HID Replacement bulbs

[DanL]

Lonnie,
What light do you have - watts and mfgr, and what is the bulb configuration - bare bulb or MR11 (bulb in reflector and base assembly)?
Your comments about Brighstar is similar to what I have seen in forum posts for 18 and 21 W bulbs. but for Brighstar MR-11's, I've seen nothing about them being tougher than WA MR11's.  I have seen a post or two saying that when bought in bulk, a certain percentage of the Chinese Brighstars don't work.  I have seen plenty of posts about DiveRite bulb failures and cord failures.  Now that I've built a number of lights, I think Dive Rite has a bunch of weaknesses: choice of cord, choice of sealing gland with no decent strain relief and inadequate shock cushioning of the bulb in the lighthead.
For what it's worth, I've built four WA 10W MR-11 lightheads now over the past year and a half, and none have failed.  One has been on many cold deco dives including the Kamloops, another on two Isle Royale and a Copper Harbor wreck trips and a bunch of knocking around, another has been on about 16 cave dives now and has been banged around alot in luggage, etc.  The fourth is with a diveshop operator in Coz for cave and technical dives - that should be the real test, but so far so good.
The WA MR11 bulb is used as headlights in sport motorcycles and in ATV's.  Can't get more abuse than that.  The key there is that the manufacturer, TrailTech, puts the bulbs in a cushioned housing.
I am using PVC components for the lighthead, with a slip fit for the ballast and a foam collar cushion around the reflector rim on the MR11.  I have actually dropped this design with no problem.
Sorry so longwinded, but basically I think its a problem of lighthead design and not an inherently delicate bulb.
Pic shows lighthead.  Note light is on my left hand - interesting story.