NEU motors are the most reliable motors built, but that has the done side you mentioned.
Keep a record of your temperature readings after runs I bought one of those cheap remote temperature sensors at my LHS it really eliminates guess work, and has saved me some heartache as I tend to try to over prop a bit too much in some setups.
Mike managed to rip the wings off of one of his planes with one of theses HET motors, the go for 69$ (plus shipping) they are cheap enough that if you break it isn't all that painful. HE has put well over a KW through one of these motors on a four cell so they do seem to take some abuse, they are only rated for 850 watts on a five cell (750 watts =1 hp so Mike was getting better than 1.25 HP out of a motor that weighs under 4 ounces).
He was using a CC 100 amp ESC and a 4 cell 400mah battery to drive that motor. The CC has a current limiting setup (that you can set via computer) to keep the power down enough to avoid cooking the battery and ESC if you smoke the motor. The controller is an Ice 100 with the dual heat sinks after what mike showed me for data he could get from the ESC I had to get one myself. I bought the same set up to go in my own version of Mikes hybrid Delta Flying wing that he found the Vne of last year.
Hopefully I will have it done soon doing built up elevons for this size airplane is a nightmare, all in an effort to reduce weight.
For what it worth as far as the electrifly motors I have one that is slotted to go in an electric SD that got pushed aside to build the hybrid delta flying wing that I am working on. I have every intention of running this electrfly 28-56 3200Kv motor on a four cell at about 1500 watts if I can keep the temperatures low enough, so that it has a chance to survive.
That plane looks so slick, I can't wait to see what you can get out of it.