Ok heres my set up guitar>boss oc-3>jekyll and hyde>voodoo lab micro vibe>delay>sonic stomp>amp (it has no effects loop) and I play metal you know chugga chugga. So in essence I need to one that works in the front of the amp.
I second the Decimator. I have the G-String and love it and the only difference I'm aware of is the less expensive one works either infront or in the loop and the G-String does both. I can honestly say I think even me having the G-String might be a little overkill but let's face it...there's no kill like it!
Truthfully, you can get two standard Decimators for the price of a G-string, and you have more control over how much noise is blocked out. With the G-string, you have one knob to control both the front and FX loop of your amp. With two decimators, you can tailor the levels to what's needed. You may need it set higher in the front and lower in the FX loop.
But for now, grab a standard, since it seems to be what you need.