Like @bigtone23 I use rounds on my Peavey '91 Dyna and 1979 Peavey T-40 as well...Rotosound (RS66 45-105 and 45-130 for the 5'ver). I have used the Rotos since 1991 for these basses and on a couple other of my basses too. I love the gravelly sound of them. Ive actually used Rotos mainly through the 80's 90's and current. I find them a good consistent string set most of the time. Not had too many Roto duds over 40 years or so.
I generally use Ernie Ball Slinky Cobalts (2736) 45-130 on my SR5 Stingray...Rickenbacker (95511) 45-105 strings on my Ric 4003.
I also use DR Black Beauties and at the moment I have DR neon whites on my EBSR5 Stingray.