I am not sure if you are speaking from personal experience but I have both Tonga branches. caribsea and tropic Eden. Caribsea is three times heavier(for the same length of a branch) and feels unnatural (just thick lumps)..tropic Eden on the other hand has the same density as natural Tonga brannches, are porous and have lots of character. Tropic marine is cheaper for the same length of Tonga branch(because they are light) however you are right about TM sand. They are costlier.I found the look of tropic Eden more “fake” look. But I have heard the sand is better but more expensive
please note: I am not even remotely affiliated with either companies. Just an honest opinion. Hopefully this will help fellow reefers know the options and pros and cons before buying sand or reef rocks.
sam