These all are late season varieties. Wonderful originated in the USA, the tree others were developed in the USSR/Turkmenistan. I grow all of these with the exception of Wonderful. Wonderful fruits came from Manuel Jimenez.
Gissarskii Rozovyi makes very large pale pink fruits that are prone to cracking. The arils are large pink with very soft seeds, sweet-sour intense flavor. Very good variety for back-yard gardeners. It is possible that these variety does not require hot weather for successful ripening, as this was the best tasting variety in the "cold" summer we had in Davis, CA few years back.
Desertnyi produces medium-large fruits. Very intense complex flavor. Sweet-sour, large dark arils with soft seeds (a bit harder than Gissarskii Rozovyi). Probably the best tasting late pomegranate.
Wonderful is Californian commercial variety. Large fruits with complex flavor, mostly sweet with some tannins. The arils are medium in size, dark, with hard seeds. Good standard variety, but I eat it when I ran out of the other poms I grow.
Sirenevyi produces very large pink fruits in late season. The arils are large, very sweet with a little bit of tart flavor, and very soft seeds. Another favorite of mine.