a package is only as good as its components and the end result being what you want:
AS in I spent x amount of money for a build of my ls3 to be naturally aspirated at about 550 crank and still get over 20mpg hwy and not have to worry about parts replacement of failure of supercharger, let alone the lack of forged bottom end, or lack of fuel economy or lack of a supercharger oriented cam.
If I had done a supercharger build what would it entail? forging the bottom end/pistons, or just a slap on supercharger and blessing to the whole rotating assembly by maybe sprinkling a part or two such as a ls2 tensioner or a cr5 timing chain? it does matter as if I am going to hurt my economy that bad, hey why not make the 660 h.p. naturally aspirated engine supercharged? and get even more? or why not not blow the rear end to smithereens and do a lot of upgrades to the suspension which I am with out even having to do more for a blower upgrade and then thinking afterward well I should have built the bottom end and that piston would not have melted or yada yada with the airfuel leaning out form needing better fuel pump and tuning and sprayers etc........ Its a lot to take in.
ANd with a supercharger it gets into a heavy can of worms of heat soak issues etc, and the gain to 660 h.p. with a ls7 is much more cheaply attainable than a 13k package, if I can gain to 550 from 426 with a cai, long tubes a tune and a cam and the cost is a few thousand going from 505 to 650 should be comparable. And that's a little step for a ls7 build N/A. so taking it all into account, well I would most likely say the supercharger is more likely a better deal with the parts involved unless its a lot more extensive build to make the whole rotating assembly forged for the n/a setup thus leaving you more strength for forced induction in the future... And well option three, I would rather have the money and not the z28 as my cars a daily driver, and a z28 would be a investment to sit on not alter for my grandkids future resale............ lol
2013 2ss/rs NPP CRT, Forged 428 ls3 stroker, Mast windage, GMPP ported heads, Katech chain, Trunnion upgrade, Cam motion stage 3, SP headers, Vmax PTB, Monster c7 dual clutch, Mgw shifter, Fluidampr 25%UDP, CAI induction, rocket racing wheels, clutch reservoir, bmr toes and trailing arms, Lpw diff cover , scanner, drl's led /fogs, elite catch can, MRT louvers, tint, ZL1 spoiler, stripes & badging, etc....