So I brought all 3 basses to practice last night. We are a classic rock band - 70's era, CCR, James Gang, Eagles, etc.
I set my amp flat and cranked up the volume, then tried each bass.
Peavey Cirrus with Chromes
I love this bass. Playes so smooth and sounds full. But, It got a little boomy on the bottom and disappeared above D. I couldn't hear any fills or runs very well.
I rolled to the neck pu, cut my trebble a lot, boosted mids a tad, cut bottom a smudge, added a little gain, and got a polite warm and even sound.
Squier VM Jazz with Sunbeams
Much brighter (happier) sound. This is my favorite bass for Contemporary Christian, but it just didn't have the presence to handle 3 guitards playing classic rock. Maybe with some eq fiddling it would be better. But it has a long way to go.
Peavey Fury (P) with Deep Talkin Flats
Eq flat, tone rolled off 75%.
Tight, thumpy, full up to a high C.
Tone all the way off and I was slinging mud like Pino.
Simply awesome sound.
I changed to Chromes, and got a similar warm sound like from the Cirrus, but lost the tight thumpy sound.
In the end, I can confirm a universal truth.
P bass with flats is perfect for rock.