All right I'm in a bit of a tight situation, now, first off I completely ADORE my tone that I'm currently getting from my JS100 but I want ALOT of more sustain especially on feedback since

of course if i buy a JS100 best chance im a satch fan

now, ive been recommended a fernandes sustainer, but that requires you to not only route but replace the neck pickup WHOA MAJOR TONE CHANGE, yea, and I've heard certain pedals can do this but i'm not sure which ones

can anyone propose the best way to sustaining my tone without changing it?
If you can live without the neck pickup then those Ferndes Sustainer and Sustainiac things work great.

Other than that you get some more sustain with feedback, and as far as feedback goes thats just in having a loud amp with a decent amount of gain and knowing how to control it right.

Compressors also work.

You can also cheat in a bit more sustainy type sound with some delay/reverb.
an EBow is the only other way I know of to get infinate sustain. It works in a similar way to the fernandes sustainer but it's seperate from the guitar and you have to hold it on the string. Only problem is it will only sustain one string at a time.
has anyone ever used a boss compression sustainer?

does it really sustain that much that i need?

i got recommended that too
Well im guessing since you dont want a new tone you probably shouldnt get a new distortion pedal. Although i just bought a MI AUDIO TONE ZONE, and i can get a sound like my Marshall but better, i wouldnt know about the Peavey (its a peavey right?) because i dont have one and therefore dont know how they sound. If you are maybe thinking of that i strongly recommend it, it has great sustain and is the BEST distortion ive ever played on. My best advice though would be a compression/sustainer pedal. They can give you lots of sustain, i wouldnt get a reverb to do it cos (from my experience) it could make it sound pretty bad. Dont have a delay pedal yet so couldnt say about that.
Nah, compressor/sustainer pedals won't hold a note for you, they just squash the decay time of the sound so the volume of the note drops slower.
The eBow is pretty sweet, and the Fernandes sustainer should work fine for any guitar, so long as it has a flat top, the pickup only makes it better. By the way, the eBow is a little harder to use than it looks,but its still sweet.