I love the Optima flatwounds so I wanted to test these Gold roundwounds too. Unfortunately I was massively disappointed.
-These strings are the stiffest and most uncomfortable roundwounds I've ever played. The feel like AT LEAST 50-100 even though they're just regular 45-105. They also have a very rough surface out of the box. I don't know if this gets better over time because after a week I'd had enough and threw them in the thrash.
-Tone. I was expecting these strings to be on the bright side of things (I don't know why, I just did...). Well, they're not. They're actually quite dark but NOT in a fat, warm way like a good set of flatwounds or pure nickel roundwounds. No, these Optimas are nothing like that. It's more like a bright stainless steel roundwound without the zingy highs. Almost like a "blanket in front of the speaker" effect. 'Dark yet thin. These strings are simply very dull sounding. I've never heard anything similar from ANY other bass strings. It feels like they're holding back on me no matter how hard I dig in. Very lifeless dynamics, very weird.
I honestly don't think I've ever played a set of bass roundwounds I liked less (well, except the strings Thomann installs on their cheap Harley Benton basses but those strings are so poor they don't really qualify as strings, more like scrap metal!).
Anyway, these Optima Golds are stiff, uncomfortable, rough on the fingers, dark yet kinda thin sounding. Very dull sound, very flat dynamics, very uninspiring. Except for the flashy looks there's absolutely nothing I liked about them. They were a huge disappointment after the wonderful Optima flats.
Like I said, I threw these strings away after a week or so. There's always the chance that the sound could have settled into something nicer over time but I played them a LOT during the week and I heard no signs of improvement. They just stayed dull and lifeless. And besides, my fingers couldn't handle the combination of stiff feel and rough texture anymore. Anyone who thinks the Roto 66 steels are rough should check out these Optimas... or rather not!