When those monte carlo scenarios were originally done and then verified again in the late 90's, they were calculated for a standard retiree with a standard life expectancy.The models were not calculated to include someone retiring at 45 with a standard longevity. 

We recently installed allure with stick strips, so I can't speak to longevity. 

Might aid tenant longevity too, but I haven't really seen that occurring...Caveat being that I own B+ places and rent to pretty decent ppl. 

As to your zip code question, our philosophy at Panzera Realty is that we encourage our investors to buy in school zone zip codes for tenant longevity and property appreciation issues, among other reasons (we want our investors to stay away from C & D properties).

There is also the PIA/longevity factor, a trouble free tenant there for a while vs one who calls you all the time, this does not contribute much but does contribute some.

That determines the strength and longevity of the asset over time.      

Any word on longevity/firmware/etc?

I chose to go with the higher quality stuff for longevity and peace of mind.

Although there are a lot of 2Br properties in this area, I think it really limits your potential rental pool and all but precludes families which tend to have more longevity.  

Very little longevity for those who fail be build systems and operate in a legal and sustainable manner.