Honda CRF450

• "Fits perfectly using all the stock hardware; mounts up in just minutes without springs. Bottom-end pulls super strong and carries over to a very meaty midrange. You can really feel a big difference in third and forth gear as you can carry both gears longer with less clutch. The power curve allows you to use the torque; you can lug the bike much longer. Top-end power is solid, but the most noticeable change is in the bottom and middle rpm range. This exhaust was one of the favorites in rough conditions" - Dirt Rider June 2005
• Rated 98 out of 100 by Dirt Rider June 2005
• Rated 5 stars by Motocross Action April 04 issue
• "This pipe rips. It makes the stocker feel like a mild-mannered trail bike by comparison" - MXA 
• No one knows the charm of the CRF450 better than Doug Dubach. Not because he races one, but because as Yamaha's official test rider, he spends a thousand hours a year testing YZ-Fs against CRFs. He's probably written more "CRF verses YZ-F" reports than all the magazines in the world. -  MXA April 2004
  

Honda CRF250

• "A" for overall rating - Dirt Bike August 2004.
• Dyno results in Dirt Bike August Issue: Stock 27.7hp:DRD 29.7hp
• "DRD pipe smoothes out the CRF''s power" - Dirt Bike August 2004
• "A" rating for fit and performance - Dirt Rider July 2004.
• "This system has tons of usable roll on power and was liked by our novice and Pro testers" - Dirt Rider July 2004
• "Electric is the word that comes to mind when riding a CRF250 with a Dubach exhaust" - August 25,2004 

Kawasaki KX250F

• "You''ll be hard pressed to find an exhaust system for your KXF or RMZ that works better . In fact, if you''re not concerned with showcasing titanium at your local track, we recommend you look no further!" - Transworld Motorcross Oct 2004
• "You do not have to be a genius to know Doug Dubach knows a thing or two about four-strokes" - June 2004 Dirt Rider
  

Suzuki RM-Z450

• ..."The Dr. D exhaust really comes to life in the midrange; the power is much more usable there.  It pulls longer, requiring less shifting.  Top-end power also pulls longer before bumping the rev limiter." - Dirt Rider magazine, June 05 - 97/100 points 

Yamaha YZ450F

• "If you own a YZ450F, The DRD exhaust is the best for it." - MXA July 2004
• "If we had to describe it, we'd say that DRD turned the YZ450f powerband into a more potent version of the Honda CRF450 powerband. God Bless Him." - MXA July 2004

• "This is the best 426 pipe we have ever tried" - Cycle World