There are a couple of things you can try for slow data speeds. A different radio/RIL pair may help, and you might also try the rcdata.img fix for TMO. First post in the Sensation radio/RIL thread has more info. I do not know if it is compatible with the MyTouch, we just figured it out for the Sensation. It is flashed through bootloader with a PG58IMG.zip file that contains a file named rcdata.img. There are two different versions, then you match a build.prop setting to it.
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