LED Bulbs ad nauseam

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   Fair warning - I'm an engineer, what's worse and electrical engineer who has developed LED lights.  I'm interested in getting to the bottom of this whole LED bulb thing.  What have you seen, and how long have they lasted?   First some background. One thing to remember about LED's is that they hate heat.  Most of them are destroyed if they spend anytime above about 120C.  They are also less efficient if they heat up.  The largest problem is that there is a conflict between a light fixture for an incandescent bulb, and a light fixture for an LED bulb.  For a regular bulb the fixture typically covers the bulb to prevent burns and breakage.  However a LED bulb needs airflow.  So the correct answer to changing to LED lights is to change the whole fixture to an LED fixture.  At that point the LED will get lots of airflow, or metal surface area to dissipate the heat.  Most people probably don't want to go that far.  I see lots of LED bulbs for the 921 socket, most of which are clearly just three (or multiple of) LEDS in series with a resistor to limit the current.  If they are mounted on a bare circuit board, they really have no way to dissipate the heat.  Therefore they either don't put out much light, they reduce the light as they heat, or they simply burn up when hot.  Now I have done just this in the past in under-cabinet lighting.  The LED's last for about 5000 hours rather than the rated 50K hours.   However these didn't have a plastic cover over them.  I expect that with a cover the 5K hours would be greatly reduced.  Maybe to 1K hours.  So here's the flip side - does that matter?  Maybe 1K hours is enough if you only spend a few weeks a year in your RV.  BTW that's with a bell curve, 1 hour to 100K hours is possible.I'm really tempted to design a bulb for my camper, but I keep reminding myself that I lose money when I do things like that.  So I'm wondering what others have done, and what the results are.  
 So in that vain I selected an LED bulb for my camper, and I'll share what I've found and let me know what you have found.  Here is a link to the LED that I used:
http://www.homedepot.com/p/t/202514337?catalogId=10053&langId=-1&keyword=led+bulb&storeId=10051&N=25ecodZ5yc1v&R=202514337#customer_reviews
It's about $11, but it has a ceramic housing that helps remove the heat from the LED, hopefully.  It's nice and bright, but a rather cool white color.  Word of warning about warm white LEDs, they tend to get cooler as they age as the yellow phosphorus used to make them more yellow decays, they also loose more light to that phosphorus.  So cool is more light.  What's not so good about these bulbs is that they are too long to fit in the double socket lights, unless you bend the bracket holding the bulb a bit.  They also don't hold in the socket very well, and I might end up adding a drop of epoxy to keep them in there.  They are running at 2.4W each, so quite a bit of light.  Here are some numbers.  With the regular bulbs, I was reading 54 lux of light at the cook top with two ceiling lights on.  With those four bulbs changed to these LED bulbs I was reading 65 lux.  I added a bit of Aluminum tape behind the bulbs and increased that to 68 lux.  I'm happy with that light.  It was a bit dark in there and this is much better and not to mention a savings on battery power.   They do get warm around the base as they run, so I suspect that the life of 25K isn't really going to happen.  Although 25K is already a derated number, so it sounds like Philips is being conservative.  Hopefully I'll get 5K out of them inside this plastic fixture.  

Here's some pictures of the bulbs installed:  Note it shows the bulbs without the lens, but I really did use the lens.  