Love ours so far. We had a 8070 before this one and one is noticeably better so far, and I loved the 8070! Higher capacity, was going about 5 MPH at 70% engine load in 50+ bu/a rye and couldn't find any seed on the ground. Quieter, more comfortable cab as well. I do dislike the spreaders on this one as the old one blew the chaff into the chopper and spread it out better.
Cant speak for alfalfa seed though. We did Trefoil, Timothy grass and Red clover with the 8070, so I cant see the elevation being any worse.