there's a thread here in GC about the line6 m13. try and look for it na lang... the m13 and m9 are basically the same thing. budget version lang ang m9.
M13 = replace your entire pedal board
M9 = put on your pedal board
I've heard that some users in general do not like the dirt sounds on both machines and still use their current dirt pedals with the M13/M9. As for the other effects on the M9, i've heard nothing but good things.
Also, if you plan on purchasing the M9 here in the philippines, I would suggest you try and get in the states na lang, if you can. The M9 is around P27k locally. Very expensive compared to the US price of $399.