Are these heads any good?

[85Bowtie]

I have a set of 333882 heads I was planning on using for the 400 I am going to put in my 85 Silverado.

I read that these castings were junk, just wondering what you guys thought.

I plan on working on this truck starting around june, so far I have the following parts:

Lunati Voodoo 256/ 262, Lift .454/ .468
Edelbrock Performer intake
Edelbrock 1406 carb
Hedman 1 5/8" headers
65,000 Volt HEI distributer (if I remember right)

I plan on using stock rockers but may go roller, use Keith Black flat tops, and the rest would be machine work/balancing the engine/block. The heads I was planning on getting were the Summit steel versions of the double hump heads they have advertised for $650. I usually don't just buy a set of heads, but Chevy has so many and I don't know all the castings like I do Mopars.

I'd like to get somewhere around 350 HP. Not sure how easy it is to get that out of a SBC. I know it's pretty damn easy out of a BB Mopar.