There's no simple answer. In fact, the frame design can cost more than the cells! And it's also more critical. Solar cells themselves haven't made any wide leaps in efficiency. However, the frame can lose a huge amount of efficiency due to glare off the front, UV damage on a plastic front, elevated temps inside the panel (pretty big loss here), or... god forbid... moisture entrapment and fogging on the front and/or cell damage from moisture. And the boundaries alone... with X sq feet of space for solar, you try to use many-small-panels with a gap between them and then the cells can only be so close to the edge themselves, this compromises some of your surface area.
Bottom line being that panel design can make or break the bottom line on the installation. The possible gains and losses of different panel features can make more difference than "high" vs "low" performing cells.