Captive tonearm cable - any advantages?

Theoretically, its better to have the single cable rather than plugs, to other cable connections. If done correctly, the advantage is greatly mollified.

The best connector is no connector. The RCA interface is among the worst for damaging the signal. Or in this case, maybe we're talking about a DIN interface. Either way, it's a physical connector in the path of a tiny signal. I think it's fair to assume that Clearaudio uses "good" wire. The benefit of getting rid of the connector far outweighs the fact that you would be deprived of choosing a boutique interconnect to mate to the output of the tonearm, IMO. When possible I always re-wire a tonearm to achieve a straight shot from cartridge to phono input.

My TW 10.5 tonearm has cable wired directly into arm less connections better sound.This depends on the cable used before i was using Purist the cable that comes with my arm is better in my system.

All else equal, the absence of connectors and solder joints is better, as Stingreen and Lewm have said. In reality, though, all else is seldom equal. The Graham Phantom Supreme has three joints before you even get to the cable (leads, wand, DIN) yet it sounds superb--better IMO than my Triplanar VII, e.g., which has a very good captive cable. I owned a Clearaudio Universal for a few years, which has a captive cable. I always thought it a bit thin and edgy, and wished I could have tried another cable. Unless you have concluded in advance that the captive cable in question is what you want for a given arm, you might find it to be the weak link. So, despite the degradation they introduce, connectors can be the better option.