Update on 271, Rubber and Flat Black Dressing. I keep trying other stuff and keep coming back to this for hard plastic, except for the wiper cowling. For some reason it won't keep that dark and good looking. On my other black plastic it seems to be superior to most other stuff. (Have not compared it to PERL - have some on the way.)
However... one negative I did notice. I did have the black trim on the back of my LR3 with 271 and half with Blackfire AIO Trim and Tire Protectant. After a few days the 271 side had noticeably more dust on it than did the Blackfire side. This may be one reason to use BF vs. DG. Sorry DG fans - hate to give a negative report.
Note that I prefer 271 in every other way - goes on easier, doesn't run, doesn't look blotchy, etc. BF is good a well - I just find it harder to apply, it needs more time to dry, and may need several coats to get even coverage. Still using 271, btw. Price to performance on a car with a lot of black trim, I can live with the extra dust.
Hmmm... maybe a light coat of BF a day or two after a heavy coat of 271 would solve the dusting problem... need to test this.