Hi,
G-force is very simple to program and easy to use, with a clear big display, with solid construction material. With g-force you can explore new sound (more shi-fi sound) and recreating some cool delay effects like Balleria 12/24 but it isn't a real harmonizer. The wah is a post effect filter and use it after preamp is a bad thing. So, i've sold it 2 week ago because $900 are too much if i use only 4 simple effect.
now i've bought a g-major. it's very cheap if you put it beside the g.force. It's more plastic made (imho) and don't have many possibilities of routing blocks or matrix modifiers (like lfo, adsr etc) but i start to appreciate it. it's cheaper and do it's dirty work.
For what i've experienced, both multifx don't work fine with a pedalboard like behringer. Wait, they works, changin effects and so on, but some issue don't work properly at 100%. Buying a used fc200 i've solved all the problem. Now i've only 1 expr pedal but in next future, i can buy another one or 2 other and i can connect them to my pedalboard. There are many connections.
hope i can help you.
instead of g-force i would to try lexicon mpx g2. not simple to use but with 2 eq (post and pre) and chosing to put wha filter after or before the master signal...it allow more experimentig tone and also a professional sound quality.
Ciao