I got a DG last year and haven't heard or had any problems with it. Out of curiosity, what bad things did you hear about it?
I read on other forums they are to loud and that they need to be repacked soon after installed. These were mufflers used on other than TW's. Bad news travels fast so I am sure it is the guys that got bad ones bitched the most. Also the stock muffler I scored was considerably less in price and that influenced my decision.
BTW, did you notice an increase in performance and or gas mileage? Did you have to re jet the carb?
Mid range seemed better to me according to my butt dyno.
With the end cap off, top photo, I too felt a little better performance going up some hills -- I made it in 5fth gear where as before I needed 4th a couple of times. Gas mileage remained the same.