I ran a set of fully ported Zeeker heads last year and they flow very well.

They are the predecessor of the Indy 440-1s. Indy bought the molds/rights from Zeeker. The only change I know the really made to them was moved the oiling from the standard thru the block to the heads up through one of the rocker shaft bolts to from the back of the block via lines to the back rocker shaft bolts. Other than that they have pretty much the same port design, chamber, rocker off-set, etc.

Actually if you by Harland Sharp rockers for Indy 440-1s the part number has a "Z" in them because they were designed and built for the Zeekers not the Indy -1s. So the rockers are the same. The set I had had the rocker pedestals cut for big lift cams so the shaft didn't fit/sit into a saddle on the head, rather they had blocks that encased the shaft and fit flat on the rocker shaft pedestals.

I heard some had porosity issues but mine didn't. They worked just fine and were a great flowing head.

Here are a few pictures.