I used 3 Limo bulls on a 50 head of Simmental and Simbrah herd of cows and the offsprings are great, have a Limousin appearance. Heifers (almost 12 months old) have the muscularity of a male, I kept them all and are going to be bred by a Red SimmAngus bull. I keep the best 3 males and will use them with the Simmangus heifers. So your cross with Gelvieh should work almost the same due to that Simmies and Gelvs have very similar characteristics.