Seymour duncan stc3m3 question

Hi, been looking at the seymour duncan stc3m3 preamp. Seen a few people on here have had them and just after a few questions answering if possible.

On the SD website Ive seen that they may not be compatable with sterlings 3 coil pup. Total newbie question but how will i find out. I have a sterling subray4 ive tried searching to find out what it is but to no avail? Im sure ive seen on here people with subs/olps have fitted them so take it it be ok.

Also are the pups soldered to the preamp or is there screw terminals/connectors? Cant seem to find any info or ive over looked it maybe?

Thanks in advance