Except that I paid less for my FPV BF2 Typhoon $60,700 in 2007 and FG F6 $65,000 in 2010 than a Holden V8 at the time so on a cost basis I am comparing apples with apples but getting a much faster car with Brembo brakes. In terms of whether the 5.0 supercharged FPV's were any good, here's the definitive dyno test and we see HSV GTS makes a maximum of just 306 rwkw's on Rob Herrod's mainline dyno, this from a car alleged to make 430 kw's at the crankshaft and costing over $120K new here.
https://www.whichcar.com.au/features/fpv-beats-hsv-in-definitive-power-test
My stock standard FPV GT-P (cost $91K new) with a somewhat dirty stock air filter made 297 rwkw's on CTB's mainline dyno
https://www.ctb.co.nz/ and 312.9 rwkw's, (nearly 7 rwkw's more than a GTS) by simply fitting a new K&N air filter. (I can email you the dyno charts if you like, send me your email by PM) My GT-P was very, very fast. I met up with Rob Herrod for a few beers when he was over here. Nice guy. ZB is a good car but 0-100 is 6.1 seconds is only "okay"
If I make it through this Covid 19 thing okay, first order of business is to get another really fast car, (keep the Calais V as a daily driver)