As with other types of calls, what's "good" depends a lot on your individual physiology, methodology and tone preference. And, to a degree, what's in your wallet.
Having been a speck and speck call junkie since moving to Southwest Louisiana in '83, I'm certain the list of speck calls I've auditioned is over two dozen long, and I currently hunt with both a small-gutted acrylic RNT and a big-gutted hedge Riceland. But someone just starting out might find it easier to get a handle on speck calling with an inexpensive small-gutted call (takes less wind), and in that category, my picks would be the poly RNT and Haydel's SP-04. Both are about as easy to run as speck calls get, with the functional differences being the RNT's greater potential volume and tonal range vs the Haydel's inherent "scratch". (Some speck voices are clear as a bell, while others have rusty gate scratch that takes more effort to imitate with RNT.)
Or, if you you're anxious to try your hand at running big guts without breaking the bank, Riceland offers a $65 poly.
If you think I'm wrong, you might be right.