Basically all that matters is that your HD receivers are picking up one of these three configs:
Western Arc 110 119 129
Eastern Arc 61.5 72.7 77
Hybrid Arcs 110 119 61.5 72.7
Hybrid arcs with those four sats works okay unless you need international/spanish programming, and some locals are on 77 or 129. Whether or not you want EA or WA would also depend on your locals.
The fourth configuration, is what they are trying to phase out, because it can't get all HD:
Hybrid Arcs 61.5 110 119
Spanish channels are now also carried on one of the EA satellites also