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.
As a kid I loved Deathscythe and Epyon, though I only ever got the Epyon kit(3 times!)
they made a new epyon kit this year that’s supposed to be incredible