if you are going SRT then get the Grand Cherokee. its by far the best SRT vehicle.

but you if you have to choose then the 300 is the obvious choice. The interior is nicer and made from a higher grade material than that rubber crap in the charger, the car is slightly faster due to less weight. The exterior of the 300 is nicer with the HIDs and subtle chrome features and the nice 20in stock wheels. all in all the 300 is the nicer vehicle when compared to the charger