I want to let you know about my first experiences with my new Boss ME-70 multiple effects pedal. Maybe this can help you with your own choice of effects. First of all, I was NOT looking for expensive high-end effects. I'm not an effect guy anyway; my preferred setup is a tube amp with a wah-pedal and a booster/drive-pedal between the guitar and the amp. I usually use a cry-baby wah and a Hughes&Kettner Tube Factor.
OK, having said that, there are occasions where I need some other effects. When I play more commercial stuff it's nice to have more sounds, a bit of chorus, delay, maybe an octaver. So I checked out some effect pedals and soon it became clear to me that for my purposes a multi-effects pedal would offer the best value. After some research and testing, my two favorites were the Vox Tonelab and the Boss ME-70. And these are the main reasons why I finally went for the ME-70:
- the ME-70's user-interface works better for me
- much better sound when plugged directly into a PA (maybe this was only because the ME-70 is much easier to tweak, but then again this is a good reason to get the ME-70 ...)
- I like that the expression pedal always acts as a volume pedal when switched off
- I could get a better clean sound from the ME-70 than from the Vox (another user-interface problem? ...)
Anyway, I think that there are not many general guidelines when looking for an effects-pedal. Nowadays almost all of them deliver good sounds if you know how to adjust/program them well. It mainly depends on what you actually need it for, which type of amp (or no amp at all?) you use, and if you're looking for special features such as a USB-output for recording etc.
If you like, share your ideas and opinions with me. Good luck with your own choices!