Tow: RR, Srt8 Jeep, or ML350 Bluetec

Hey,
I am looking for any real world experience with any of the following vehicles for towing. I have a 2010 Mastercraft X25. I would be towing between 40 and 100 miles each way, hopefully only at the beginning and end of the season.

2012 or newer Range Rover (the full size)
2012 or newer SRT8 Jeep
2012 or newer Hemi Jeep
2011 Mercedes ML350 Bluetec (Diesel) (my current vehicle)

I thinking about getting a new car. Currently, the MB is not set up for towing. I can set it up though. The marina I store my boat with has been coming to get my boat and bringing it back, but I'd like to have something to tow with just in case they get backed up and I need something done mid season.

I am not thinking about a truck. I like the idea, but just couldn't do it. Please do not recommend a truck or a different SUV not listed.

Also, I realize the RR's are prone to breaking down. I just read somewhere that they are excellent at towing (I read they were designed to tow horse trailers) and was wondering if they were really all that great at it.