Now that my Ram is three years old, it will likely be due for a pair of batteries within a couple of years (or less). In the meantime, lest if do not change them prior to failure, I am considering a jump starter pack that is capable of reliably starting that beast. The two I looked at are the Clore JNC660, JNC770 (same ratings as the 660, but added features), and JNC950 (maybe a bit of overkill, but I tend to "over-engineer stuff). Looking for those with experience and recommendations, please. Thanks!