Mine is pic related, the Victory Gundam. What I like about it is how modular the mobile suit is. It's the result of years of ms tech late into the Universal Century where now the Gundam is mass produced. In the show the rebel forces are shown to have a stockpile of Gundams in a bunker so they can burn through parts.
Honorable mention to the RX-79 G ground type Gundam from 8th MS Team.
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the valkyrie turned into the transformer jetfire! it was also stolen for some battletech mechs, as were a bunch of mechs from fang of the sun dougram and crusher joe! the rights to macross are a mess