I ran the 509 in my current 440 , it likes stall and gear plus compression. I started with a 4200 and 3.9 gears , ended with 5000 and 4.1 .
I also tried that Lunati when I went sft , it was good but not noticeably better on the chassis dyno , though I never ran it at the track . Had a fabulous loud sound , even louder than the 509 . I also fitted the Lunati in a 510 stroker and another 440 both ran great with rump .
The Lunati was great on the street .
Surprisingly I also had the 509 in a 8:1 440 , but it also had the 4200 plus 3.9 gears though I also had 3.54 gears at 1 stage .
I always run a 29" road tyre , 28" on the strip .
The 509 also did a couple of interstate runs , 12hrs each way , no worries .
With the tight lobe 509 there is no engine vacuum for brakes especially with a single plane intake .

Tex