I looked at Superior Bassworks Deluxe DIrty Gut, but I gather they're not loved here.
I guess it depends on who you talk to about the
Superior Bassworks Deluxe Dirty Guts. I've used their medium gauge D and G with SilverSlaps E and A for about 5 years and really enjoyed them...
Then about a month ago I moved to the thickest and highest tension full set of SBW Deluxe Dirty Guts and I'm totally thrilled with them -- but they're really thick (E .170" to G .105") and that may take some getting used to for some folks. They're about as thick as a full not-wound set of real guts, with a similar look and feel.
While I'm sure nothing synthetic sounds exactly the same as real guts, the thickest SBW Deluxe Dirty Guts do come closer than either Golden/Silver Slaps or Sugar Slaps in tone (I've used both). I was seeking that old school gut-like tone, and that's what I get now.
Most folks assume Deluxe Dirty Guts probably were born as some sort of wacker and that's why they get a bad reputation. But they are definitely not wackers anymore.
They are bullet proof for hardcore slapping, they sound great either acoustically or amped, they even bow well (which neither Golden/Silver Slaps or SugarSlaps do). And for $70US, it doesn't take much to give these a try.
P.S. ...
The Sugar Slaps aren't too expensive; how do they rate?
I tried Sugar Slaps for about a month, until they snapped just outside of my custom tailpiece. I really liked their tone, but it's a modern tone compared to a not-wound gut set. Under perfect conditions they might workout fine, but I've heard other people express that they had them snap unexpectedly too. I would be concerned that they are too fragile, especially with rougher play like heavy slapping. Oh, and they are not bow-able.
As mentioned my previous main-stay was a mixed set of SilverSlaps E and A under SBW Deluxe Dirty Guts medlium D (.105") and G (.095"). This mix was a very good match in tension, tone, volume and feel. I started to feel like it sounded too modern on my Alcoa though, so that's the main reason why I moved to the fattest Dirty Guts. My SilverSlaps were UK-Innovation SilverSlaps and I never had any problems with them, but the newer GHS-Innovation strings have had a number of reports of winding problems. And also, Golden/Silver Slaps have difficulty speaking with the bow.
FWIW, the thickest SBW Deluxe Dirty Guts that I'm using now (E .170" to G .105") are slightly higher tension than either SilverSlaps or Sugar Slaps.
Lastly, early this year I attended a week long workshop with Edgar Loudermilk, the bassist/lead vocalist/front man for the Edgar Loudermilk band. He uses Zyex mediums and they sounded and felt excellent on his double bass. He plays aggressively and has broken Zyex lights, but the mediums didn't feel very high tension at all to me. I'd be tempted to use them, but they have a modern tone, and also I avoid metal component strings in an effort to reduce metallic tone on my Alcoa.
Strings are a rabbit hole. I've been lucky to have really enjoyed some strings so far, enough to stay with them for a long time.
I wish you the best as you figure out what you like!