Ronnietex...as LimaGuy mentioned, I use strictly flats on all of my SPECTORS. Also so does seventhframe. Ive tried rounds from different manuf. just this week I tried some DR Black Beauties they're coated nickels, didn't like them. I've used D'Addarrio chrome flats, okay but not quite the sound I like. I keep going back to GHS Precision ground Stainless Steel Flatwounds. I've used them for over 3 years now, you don't lose the SPECTOR growl, IMO, it makes the growl a lot more noticeable. They have a big sound. Plus they are smooth as silk! You can play for hours & hours and not have bloody sore fingers. They have a very longevity. I've not had any troubles with dead spots. I play in 2 bands, they're both are Christian Rock bands. One is really quite rocky! I dig into the GHS's pretty hard and they keep on taking it!
A friend of mine plays in a local Rock cover band, plays a 72 Fender P bass and swears by the same strings too. Been using nothing else for years. Sounds like you already like flats so put on your SPECTOR! You'll not regret it!
P.S. If anyone's interested, I have a set of DR BB's with about 2 hours of playing time on them FS! PM me! I'll make ya a great deal!!!