I vote for the Bowman Hobbies Sonic. It is the most versatile wing, and has the widest aerobatic envelope PLUS the ability to carry energy at modest weights (say 17 to 25 oz, depending how you build/cover it).

I've flown All manner of Zagis, the new popular Windrider Bee and Bat wings, and the Cavazos Boomerang. The Sonic shines above them all IMO.

In case you don't know who Pat Bowman is, he flys regularly at Parker Mt (the birthplace of DS soaring). Before he introduced his now popular JW, the Sonic was his catch all aerobatic machine that can also DS fairly well.

Pat has the benefit of also flying regularly with Joe Wurts. I believe this high pedigree shows in the performance of the Sonic.

If you want to stay up in the lightest lift possible, get a Windrider Bee,and cover it in tape (not the fiberglass reinforced variety-- the thin colored stuff). But for everything else, the Sonic is my "must have machine".

(if we expand the category to non-wings, then the DAW SW 1-26 is THE MOST versatile EPP plane I can highly recommend, but that's not a simple wing, and you didn't ask for non-wings, right?)