I tow a 34ft 14000lb 5er with my SRW and am very happy with the performance. Still, mine is a 2013 (after all manufacturers beefed up suspensions and payloads), yours is a 2004 so I'd be concerned about payload of your truck first and foremost. The long length might also be a factor pushing SRW around a little where DRW would add more rubber to road to counteract. Some would be comfortable with the later, some not. But again I'd look at your truck payload pretty hard.
Maybe it's a reason to get a new truck :)
