I've had two 3rd gen Dakota's and one 2nd gen Dakota. The magnum 5.2/5.9 is stout in stock forum. I have a beater 1996 Ram 1500 with the 5.2/NV3500 combo that I paid $900 for, haven't done anything to it but change the oil. I put 15K miles on it so far, has almost 190K miles on it now. I'd drive it anywhere.
My Club Cab Dakota R/T was running 12.4 @ 111 on motor with the STOCK 112k mile 46RE automatic transmission. Yes, chrysler transmissions aren't the best in stock forum but with routine maintenance(Which seems most don't really do) I haven't had a problem.
My current CR Cummins stock 48RE transmission survived at 4XXrwhp/829rwtq for quite awhile, but I knew I was on borrowed time. Now it is mildly built and have a lot more power than I did when it was dynoed last with the stock transmission.
The Magnum V8 / NV3500 combo is fun, but a weak transmission if you start making more power. If you're leaving it stock it'll be fine.