Check out Dirt Bike mag August 2004. Its got a white cover with blue letters. It has a full article comparing noise to power for stock plus 5 other exhausts, including Dr D. Basically, only Dr D gives any real significant power boost, 2hp, for the price.
I'm going to San Felipe to ride for the first time in a few weeks and was hoping to get any tips, advice, suggestions whatever on riding off road and traveling in Mexico. Thanks for the help in advance. Looking forward to breaking in my new crf250x. Should be awesome riding on the beach on the Gulf!!