I don't know anything about the merchant so I can't help you there but as far as the 24" bike thing. I personally would do that. The 20" refers to the wheel size (rough estimate w/ tire). I think of 24" bikes as a totally different breed of rider. Like speed cycling and mountain biking. If you are looking to be like all the big names on tv like Lavin, Mirra, and Aitken you are most likely looking for the 20" bmx bikes. For dirt bikes though I would suggest either the Mosh 4 Star (haven't riddin) because of the good components and frame or the Vegas TJ (May be called the Pro now, the best one of the series anyway is what I am refering to, I say this one because I have ridden a friends at the trails and it just felt to me like it was made for trails and nothing more.) The low top tube makes over the top bar tricks like can cans much easier. I don't know about the new frames quality though, the Gold vegas of 2000 had oval head tube problems and the chainstay tubing dented easy. Sorry I am rambling on, just trying to get my opinions out there.
Oh yeah, I forgot to include the weight. When I was 14 (a year ago) I was riding the S&M Bennett. My complete bikes weight was around 36 - 38 LBS. I didn't have anytrouble throwing the bike around in the air then and you are a little bit bigger than me as far as height and weight so I don't think that you will have any trouble.
Last edited by jumpa56; 03-12-01 at 05:04 PM.