Sorry for any confusion MAGP, I'm trying to not be biased.
Thanks for your input, and yes your post did make me think about trying the higher scale MAF route, because I didn't want to waste my current NVRAM hardware and I had read in The1's write up about the larger volume MAFs and that his code works with them once scaled. which I will have to work out how to scale, as it didn't say anything more than that about getting it to work. I assuming his extended bin works as the MAF Hz exceed 16KHz
My old 1994 VR V6 with a SC14 Side-mount Toyota blower did use a Blow-off valve because it was feeding into the TB like CAPA's kits. Lucky it was MAP because it wouldn't have worked otherwise.
I'm surprised not really anyone else does Vally-cover mounted Blower kits for the 5.0L Holdens. Yellaterra do a whipple kit, but it's a million dollars for the most basic kit.
Everyone else seems to only do centriflugal blowers which are less parasitic, but miss the point of being a blower, and have a less linear boost curve compared to a roots type. so you may as well go turbo at that point.
I'm keen to test these both so I can get the mill onto the intake.... I may have to buy a spare just to play and have a factory backup.