I've only used roundwounds since I started in '94.
I don't play a particular brand exclusively, but I use Elites Stadium and Rotosound Swing '66 more often than I do others. I also like Ernie Ball, D'Addario, Dean Markley, Dunlop, Fender, Galli and Warwick strings.
I'm yet to try GHS, Elixir and La Bella. Maybe soon!
Currently using Elites on my Warwick SS (50.70.90.110) tuned Eb standard and on my Peavey Miletone I (45.65.85.105) also tuned Eb standard. Rotosound Swing '66 on Fender Precision (45.65.80.110) standard tuning and D'Addario Nickel on Yamaha RBX 1997 (40-125) standard tuning.