I have plain guts on ADG back on, with a E.P. slap E, so it`s all gut tension and med / high action. I`ve found out that more that I have guts on my bass then more logical and fluid my playing gets, as there are no huge differences in feel under the hands and intonation between differently structured strings. It`s practically easier to find a sweet spot in the string height, feel, tone and volume, for me at least. I had spiro or evah weichs with stiff plain guts on DG for some months and I loved the tone, volume and projection, but the feel was off, be that pizz, arco or little slap that I do.
I have now Efrano mediums AD with a trusty Chorda G on. I need to play the Efranos in since I`ve had them for some time without checking how they really work when / if they open up. I need to keep them on for at least 3 months, and several circles of maintenance, I think. Another big issue is to relearn the system of playing those chunky bastards and bow them a lot to learn the symphatetic resonance and intonation, which I`ve found beeing easier when there`s more plain guts involved than only G or DG, and sounding really cool, at least accidentally sometimes

Sustain comes only with correct intonation, that much I learned from my previous crusade, I have to be in balance with natural resonances of my bass, no less.
Needless to say, besides strange rehearsals yesterday, I`m hooked again. There`s nothing like them, the deep colourful tone, like timpani when played pizz, like reed or voice arco, smooth bouncy feel. It will take time anyway