My first shotgun came with the SureFire fore-end and I really liked the bulk--it really has something to grab hold of.
Then, I sent my Wingmaster to Wilson to have it built to Border Patrol specs, and I too was concerned about the "dinky" SpeedFeed fore-end. I even asked Wilson if they had a bigger one. They didn't.
My fears were unfounded. I can fire every bit as fast as I can with the fuller SureFire, and my hand never slips . I even tested 3" Federal slugs rapid fire--whoaa! Hand stayed there, worked fine. Looks like SpeedFeed knew what they were doing, afterall.
Just don't try to confine your thumb and fingers to the smaller indented portion. Grab ahold of the whole forend.
If you've already tried one, and you don't like it, then proceed with rounding up another one. I liked a Combat fore-end by Remington, I saw. But, if you haven't actually tried it, you might be surprised. Bet you'd like it fine.