W2 Head Flow Numbers - Need Advice

Does anyone have flow numbers for ported and unported W2's? I was wondering what the flow numbers should be across the range of lift for either ported or unported for comparison. Here's the reason I'm wondering. When I bought the car, I was told that the heads had been ported and the guy that bench flowed the heads showed 321 cfm. I don't know what lift or the bench that was used. The guy who has my motor now bench flowed the heads somewhere around 250 cfm @ .500 lift with a 25" vacuum on the bench. Even doing the conversion to 28" vacuum that is normally used, those numbers aren't even close to the numbers that were previously stated by the other guy. Why he didn't take it to .700" lift, I don't know. I think he thought the heads wouldn't flow any more over .500". I want the heads to make as much power as possible so what I'm wondering is, should I be concerned at all with maybe sending the heads to someone who is good with porting and take a look at them? Have them flow test on their unit? Or should I just not be concerned over these numbers that don't seem quite up to par with what I've seen on ported W2's? As long as it makes the power, who cares? What are your opinions?