After reading a lot of user reviews I have to make the hard decision between the MXR or the EHX. MXR: the killing feature is having two separate controls for the clean level and the effect, this way you don't get lost in the mix. Qballs: More effect posibilities (High and Low Pass, Start and Stop) but only one control for the mix (no volume control). I read some issues about volume drop (I don't want to spend even more cash on a boost) and levels too high for the distortion. Has anyone compared these two?