I like doing business with Jab-Tech. The PET lists a decent working temp. It will survive the heatshrink being worked. If charlietee rates Techflex highly I would not contest it.
I used some cheap blue sleeving kit from SVC in my sister's build and was really disappointed. The mesh could not endure the heat gun and the shrink curled like blue baloney

I've had years of automotive experiance using shrink tubing, so I do know a little on the subject.
I'm not concerned with lighting effects as much as some. I've been using 3M black sleeving and shrink tubing. Bought it from action-electronics. They also have fiberglass lined sleeving that is for very high temp applications. 3M is amoung the best.
I bought my heat gun from Harbor Freight for $10 on sale, now it lists for $15. It has two settings, 600 and 1000 watt. Nice to have but not requiored. I would not use it to strip paint but for shrink tubing it is good enough.
...Galvanized