I noticed a significant improvement in smoothness, in going to external bearings (with a hollowtech II style crank, and this was bargain-basement brand-x parts), because the bearings are larger so have more balls, possibly also bigger balls, and that makes them roll smooth. It's also a huge benefit to be able to adjust the preload to take out slack perhaps every six months, that makes a big difference in the bearings lasting longer.
I've gotten away from cartridge BBs, for the above, and because I put on a lot of miles, and it would only take a year of dry biking to start to get a tiny bit of slack in the bearings, and no way to adjust out. But if you were going premium on an internal cartridge, in addition to the renowned Phil Wood ones, SKF makes internal cartridges with their own bearings, and the crank side has roller bearings, $170 last I looked; They also say the spindle is stainless steel, excellent for seal life as no rust, but this meets specs for city and touring bikes but not racing, as the stainless can be brittle for the hardest hammering riders, they recommend someone else for racing (a surprise, as stainless alloys have advanced a lot, though most are powder-metallurgy process, which is super expensive). SKFs are 10 year warranty, but not rebuildable. If Phil Wood ones can be rebuilt at low cost by just replacing standard cartridge ball bearings, that would be a plus, but I don't know.