The MSI armor is actually a good choice.  The fans are double ball bearing, so they should last a bit.  You cant really overclock them that much, but I have a few that run at 0.89v easy.  power consumption is really low (i have 470s).  I made a review here:  http://www.cryptominingtalk.com/msi-armor-470-4g-review/

You should check out the sapphire nitro fury on newegg, sometimes its a really good sale.  Could be a worthwhile alternative to the 390 if you want to go that way (more hashing power per rig).
edit:  the last rx470 msi armor 4g i got had samsung memory.  all the others hynix.