It's not that simple. There are all kinds of variations of both; brighter flats, darker, flats, zingier rounds, darker rounds, half wounds, quarter wounds, ground wounds, tape wounds, pressure wounds, and tightly wounds...........oh wait a minute that last one is just me getting wound up.
The whole premise of a poll is ridiculous and leads to all kinds of sophomoric comments and insults from both sides. Who gives a rip besides you what you play? Do the people at your gigs come and ask what type of string you play? They don't at mine and never did.
Each one fits different playing styles, different types of music, studio recording, live performances and even different basses and amp rigs. Playing one or the other because it's "cool" or "not cool" is the dumbest thing I've ever heard and one side putting down the other is even dumber. A pro bassist would play both at need.
Some guys could play hunks of steel cable and sound good and others could have strings made pure gold with unicorn hair silks and they'd still sound like crap. It's one link in the chain and not even the most important one. That link is the guy playing the strings not the strings themselves.
Sorry to be so negative early on a Sunday morning but someone tell me just why one more thread on string preference to add to the other 1001 is all that important?