Well, I thought I had replied to this thread, but apparently not, so here goes...
The only set of strings I ever put on and took off in ten minutes were the Hartke strings that are sold pretty in-expensively. I positively think the gauge was mis-labeled and I've never felt a worse-sounding, worse feeling strings in my life. However, I had bought 4 sets, so I gave the other 3 to other bassists at my church (the ones with kids, mortgages, car notes, insurance, etc, in other words, guys that might appreciate them)...
Not one of them said anything bad about the Hartke strings. They were all glad to get them and I turned them onto the online source to buy them. Fair enough...
I use and love the Ernie Ball 5-string Power Slinkys in the heavy gauge (050, 070, 085, 105, 135). My personal experience with them is that they aren't the brightest, crunchiest set of strings out of the package, but they retain their inherent brightness for a good long while. I change them about once a month of so, although I have a set on my fretless that's over 2 years old now. They sound sooo good on that bass, I hope I never have to change them. The perfect amount of deadness for fretless playing.
I don't have a thrash right-hand style of playing, or try to beat the bass down, but I have a pretty strong stroke from playing a lot. I've tried several times to go lighter so I'd have more strings choices, but I've given up the chase. I can't imagine needing anything brighter, more or less tension, more balanced, and long life than what I have with the Power Slinkys.
I've looked long and hard for other strings in those gauges, and I may have missed some, but I haven't found other string brands that I can buy without making a special gauge order. Plus, because I have family ties with the local music store, I can get the Power Slinkys super-stupid cheap. And the Power Slinkys work on all four of my basses, I've felt no need to vary what strings go on what bass.
No flats for me, ever. I'm happy they are available for other players that need them.
Strings, like a lot of things musicians use, are a very personal choice and for very varied reasons. It's no surprise whatsoever that the same strings are loved by some and hated by others. At all.