I'll share my experience with DFC Diesel. I purchased my long block and had it professionally installed. After just 15K miles, it developed a knock in the lower part of the engine. Unfortunately, I was on a trip towing my 5th wheel and 300 miles from home. I needed a new engine now. The only offer short of “send us the engine and we’ll get back to you” which would surely take months, was that I could buy a new engine from DFC, send them the old, and then they'd determine if it’s a warranty failure or not. Considering the numerous negative Google reviews from others in a similar situation as I, I was not confident they would find in my favor, and I’d effectively be stuck with two undependable engines and be out nearly $20K after buying two engines and paying labor charges. Thus, I decided to buy an engine from Jasper who is in the USA where I will have some legal recourse if I have further issues. I’m not even willing to risk losing another $2500 by paying Jasper's core charge and sending DFC the bad engine because at most, they'd simply send me a replacement for which I’d have no use. So, congratulations DFC Diesel. You win!
I really hope you get a good engine out of Jasper, I've not heard much good about Jasper rebuilds on HEMI engines...