I've run an IBC tote system with 4 totes now, pumping from a sunken sump pump 4ft under ground up to top of another IBC - so 8ft total. Running for 1.5 years now. On my 3rd one. I can tell you this:
First pump ran a little over a year, no problems, never turned it off, etc etc. I tinkered with the system and my sump runs a little low leaving it slightly exposed, this leads to the pump melting if left out over time.
Now on my second pump, I assume the year of use is what lead to its demise, not fully understanding my heat/sump issue. Burned up my 2nd one. Called support and they RMA'd me a new one, explained if its out of water for more than 30 minutes it will burn up.
Fixed my sump issue and things are running fine again.
Moral of the story? BUY A FLOAT SWITCH!!!!!!!!!