The 44 is a stronger axle, but they cost more because people want them to replace...
The dana 30, which is too small for a bronco that gets driven hard.
The 30 also has archiec king pins on the knuckles. Good thing about a 30 is that they are cheap, if they aren't broken. A complete 30 in working order is worth $100~150. Broken they are worth the value of scrape steel.
A bare 44 housing goes for about $150, and goes up(a lot) from there. If you go cheap and get a 30, be careful. There are a lot of broken ones to be had.
If you find 2 trucks in in a yard in equeal condition. one has a 44 in it and the other a 30. Good bet the 30 is broken and the 44 is still good. Come back the next day and the 44 will be gone.
the 44 has bigger bearings, gears, housing, pricetag, everything. The only down side to the stock EB dana 44 is that they kept the undersized U-jonts from the 30, but that is easily upgraded.