Well they do throw in a helmet less hayate, tho not sure if messer is included.
So the count now is 5 walkure valks + the 31j Kai + the 31f lil draken version + the 31a (03 version) = 8 vf-31 variants to collect for those who want to complete the delta 31 collection at this point.
potentially the 31a arad and 31a (02 version) would make it 10 vf-31 variants to collect for a complete collection!
muahahah *insert the Sesame Street count laugh and thunder here*
Well the DX 31 is indeed a wonderfully engineered valk, so that's 10 times the enjoyment!
besides this can't match the number of vf-1 variants in the macross verse...