Left to right purple possum, fredrick, red rover.
Flavor wise the purple possum and fredrick are both good and very similar. Red rover has more of a unique flavor than them and tastes better to me and my wife.
Fredrick has the thinnest shell and gets damaged easier from the sun after dropping off the plant. Purple possum also damages from sunburn after falling off. Red rover has the thickest shell and will take more sun before being damaged.
Overall red rover to me tastes better and also is able to sit on the ground for several hours before being damaged by the sun. It seems like the best ones although they maybe have less edible flesh per fruit.
All 3 types grow like weeds and produce heavily.