yeah: I can't remember the last time I took a pack animal mining.
The Fire Beetle acts as a forge for you, and going around with my fire beetle and a tool assortment (usually 2 200-use sturdy shovels, 2 Prospector's tools and 6-8 Gargoyle Pickaxes), I end up with 3000 to 4000 total ingots before returning home (though generally that number includes the iron ingots that I send to the bank with a Bag of Sending every time the total hits around 1000, to keep weight down). I use a human miner with STR over 120, so my carrying capacity is in the 530s, of which 80 is my base weight, armor and other gear (chiv book, runebooks, etc.) and the rest is dedicated to harvested ingots, ore (prior to smelting), and my tools (which slowly diminish in weight as they break from being used up). I also keep one Greater Strength potion handy so that, if neccessary (say, retrieving the iron ore from the bank without using a deed, or I get a paragon ore elemental chest in Ilshenar, my favorite ele hunting area) I can carry my full 550 pack capacity back home.
10 ore = 120 stones
20 ingots (what you get from 10 ore) = 2 stone.
Therefore: using a firebeetle reduces ore/ingot weight at least by a factor of 60 (more, counting in failures)
your backpack = roughly 1/3 of a packy's capacity.
1/3 * 60 = 20
Using a Fire Beetle, with no packies, is equivalent of mining only ore, and having TWENTY packies to load ( or, 4 times as many pack horses/llamas than you can actually have).
So, you can stay out mining (especially if you're a tinker crafting your own shovels) 4 times longer without reloading, than someone using 5 pack animals.