WOW......................this stupid shower head I just got in the mail is nothing but an REALLY cheap one that has been bored out.
I put it in and it sucked.
So then I removed my inline valve and it improved greatly........but that still doesn't make me feel any better for having spent $20 on a $4 head with a big sloppy hole (have at it fellas).
So.......I put the solid brass "decent" one I bought recently back in and it works GREAT (after having the restrictor removed and also the little inline valve.
So........here is the lesson I have learned....
Flow restriction........ummmmm............restricts flow.
The little stupid valve I had in line has an internal valve ID of less than 1/4".........while the inside of my "standard" shower head has a ID roughly equivalent to the inside of the shower feed tubes/valves.
So.........there is NO need to bore out your shower head unless you have pretty consistently BIG bored supply lines/valves, etc.
Now......I'm not going to take the time to consider moving the tiny valve farther back in the feed line (using the piping as a ballast tank).......instead I just replaced the inline shut-off with a brass ball valve I had laying around.........and I have super flow with a standard head (sans restrictor washer).