The Sig Limited is the prettiest sounding guitar for me. It’s quite amazing how much sweeter it sounds ( to my ear) in the neck position compared with a first year Paul’s guitar I also have. They technically have the same pickup but sound miles apart . The Sig breaks into sweet harmonic trails for breakfast and sustains till lunch
I don't think it's a matter of the pickups alone.
It's my belief that the neck and fretboard woods matter a lot more than people give them credit for. The Sig Ltd had some unusually dense wood in the neck as one of its highly touted features. I think that's a big reason it sounded so great.
I don't know if you remember the uproar over whether the necks were in fact so-called 'sinker' mahogany, or just very dense mahogany, but Paul made mention several times that they were dense enough to sink, and that's why he referred to them that way. Personally, I didn't care what they were called, they sounded great, and felt very lively. I think you're hearing that!
I had Artist V, with a Peruvian mahogany neck and ebony fretboard. The guitar felt more alive in my hands than any previous PRS I'd ever owned (there were many), including several others with ebony boards.
When the 30th Anniversary CU24s came out, I had my dealer send me a back-to-back comparison clip of one with an Artist Package, and the PS version with a Peruvian Mahogany neck, Madagascar RW fretboard, and African ribbon mahogany back. As good as that Artist sounded, the PS was amazing, with a different tone and what seemed like endless sustain. I bought the PS. I think it's those woods that make it so different/great.
My McCarty Singlecut also has a Peruvian Mahogany neck, Madagascar RW fretboard and African ribbon mahogany back, and again, it's a guitar that became my #1 and simply sounds the business.
The 20th PS Anniversary model has Madagascar RW on the fretboard, the African ribbon mahogany back, and on this one the mahogany is thicker than usual, the maple thinner than usual. For me, combined with the pickups and the locking trem saddles, this one is a singer with a gorgeous voice.
So, yeah. It's the woods more than folks think.