I can't speak directly about the Wonder or the Shrike, but guys swear by them. There have been many threads about them done at the Extreme Speed forum. Same rules apply, if set up lightly and intelligently...you'll end up with fun planes to fly that are easy to keep in one piece. The Diamond Dust has fewer pieces and is a superior overall flyer IMO.
The launch technique is the main hurdle. I cringe to watch a friend launch. He lays his radio in his left hand, releases the plane with his right hand, then transfers the radio back to his right hand to fly it. I've suggested that he learn to launch [release] with the left hand and keep his right thumb on the TX, but old habits are hard to break.
The instructors who shudder at the mention of a delta aren't speaking from a position of experience. 25 years ago when I took my first delta to the field, the club "know-it-all" came charging up and blurted out that there were very few men in the world capable of flying these things and that I shouldn't try without expert help. Of course I didn't listen to him and tossed my OS .10 powered "Lil Toad" skyward and had a great time with those planes ever since.