I'll echo this. Birdie balls feel far more like regular golf balls than any other limited flight practice ball I've used. The ball flight is a bit exaggerated (no big deal), and it doesn't take much wind before they are unusable.
I also like the Pelz "almost golf" balls, but they still go quite far and I tend to lose them.
I don't adjust my swing for either of these types of practice balls. If I hit the really light, foam, squishy practice balls, weird stuff happens - usually a big hook.
The nice thing about the Almost Golf balls is that they are safe around glass and other materials. I have two stories and I can hit 'em in the back yard, using my house as a backstop without worry of damage to windows or vinyl siding. And they have pretty good feel and ball flight. I like Birdie Balls in an open area (and the sound they make is pretty cool).