Here's my take...
The resale issue is CHANGING. Conventional wisdom has been that the 6.4L HEMI isn't resell-able. With 3 years under it's belt in the marketplace, it's catching on and they're selling pretty darn well. So this simply isn't true.
The 2017 Cummins ask is $9,200 list, $8,700 list if Laramie trim or higher. They dropped the price on the 6.4L HEMI in 2017 -- it's now FREE for Laramie on up and $500 below Laramie (SLT / BIG HORN / Tradesman, etc...).
So that's a NET of $8,700 list difference.
2016 on back the 6.4L HEMI was $1,395 for all trims and the Cummins was $8,900 so the difference / savings was much smaller, $7,500.
So for 2017 -- The 6.4L HEMI is $1,200 less expensive compared to the Cummins in 2016.
Stoplight to stoplight, the 6.4L HEMI is quite fast.
The 6.4L HEMI is a hell of a package now if you don't need to tow heavy.
-Guzzler