I have Gold Nugget in-ground, my tree is about 10+yrs old, and it gives good tasting fruit each year. My GN is on semi-drawf rootstock. I like the taste of my GN, it tastes pretty good compared to my kishu, tango, satsumas, shiranui, ponkan, honey, murcott, Iyo mikan, kiyomi and ugli tangelo. I've been growing citrus in same house for 30+ yrs as well.
The tree is about 8 ft tall, I don't trim it much to keep it at this height. I have high density planting of my fruit trees, my citrus trees are about 5-10ft apart (with pak-mulberry, loquats, persimmons, cherimoya in-between). Valentine/cocktail/pomelo trees are about twice as tall on standard rootstock and I need to cut them down to 12 feet every year.