I've used used some "cheap" shrink tubing I got from a auto-parts store for about (3) years and haven't had any problems with it. It does have a more "matt" surface finish, so does appear "papery".
The tubing I've used came labeled "PTC" "Manufactured in China for Prosperity Tool, Inc." " Plant City Florida, USA". Each piece of tubing is stamped ""ZRG VW-1 600V" (presumably 600 volt insulation capability) and is rated for 125 deg. C. max. (no low-temp. rating).
The other brand I use a lot is 3-M Type FP-301 Mil-spec "MIL-1-23053/5 Class-1". It's also rated for 600 volts, and has a temperature range of -55 to +135 deg. C.
The 3-M military grade tubing is definitely thicker walled and stiffer, and I'd trust its voltage rating more than the thinner Chinese stuff. The 3-M MIL spec. tubing also carries RU, UL and CSA certification and is marked "Fire ******ant, which the Chinese material is not. Apparently the Gearslutz politically-correct automated censor won't let me write the correct terminology above. the tubing is marked " Fire R E T A R D A N T"
I actually prefer the Chinese stuff for connectors like DB-25s with tight pin spacing. It's easier to slide the tubing in place between the pins.
Because the Chinese stuff is thinner, it probably does not have the insulation breakdown resistance of the 3-M tubing, but for low voltage audio that is not an issue.
I've used larger diameter sizes of the thin Chinese stuff on spliced and split fan-out cables that get hard use, and, so far, its worked OK (no failures).