No such thing as too much head. As for the twisted wedges, how they affect the rpm range depends on cam choice. Just as with smaller heads. Sort of like the myth of the 4 bbl Cleveland heads being bad performers on the street. What you should ask, is whether you really want to pay for, what they sell for, for the performance you'll get, and the performance you expect.
it will depend on your total combination as to whether or not you have too much head capacity. mild cam, long gears, small carb, etc, then you have too much head. pick your components wisely and match them carefully and you will have a strong combination.
Those flow numbers are around .700-.800 lift. With the right cam and compression should be a decent power plant. but with the same cam you would have way more power with a ported high port head.
As said above, its about the total combination. The biggest drivability factor will be the cam. At this point, you should be considering a custom anyway, in which case the grinder can take the flow and port size characteristics into consideration to move the powerband around with your specific combo.
There IS such thing as too big for a street car. If it is 400+ ci, these are ok. A 347 street motor will be giving up alot of bottom end, and never reap the benefits of large ports. To make these heads work it would require a cam that will a LOOSE converter and big gear, neither are ussually associated with a street car.
How much are they asking for the heads? Are they complete and ready to bolt on? what kind of induction system do you have? How do you intend on using the car?
If you want to run a 750 Holley, a manual trans and some gears, I think it would be fine. You would definitley need the right cam, but its funny how big heads don't usually need a big cam to perform well on the street since they move so mauch air to begin with. Anyway, those heads sound borderline for that engine, but strokers can move some air. If you can answer the questions above you'll be closer to figuring out whether or not you should buy those heads.
sorta like asking is a 1050 holley too much carb for a 289 huh?
Well, just keep everything in proportion. BIG heads require BIG AIR and BIG EXHAUST, and along with more air, more fuel, comes more power, and the need for improvements in the bottom end.
Bottom line is YES, you could have too much of ONE component, that puts it out of whack with the other modifications, and tends to lead to an overall bad experiance, but in and of itself, head size is relative.
Carb size and cfm are relative, headers are a little more forgiving tho, but just remember, it's the combo that works, not any one individual component.