Same selection.
Considering the close price difference, the two additional front-facing Thunderbolt 5 ports on the M3 Ultra model offer an advantage over standard USB ports.
It’ll be interesting to see how much difference there actually is between the M4 Max (128GB RAM) and the M3 Ultra (28-core CPU, 60-core GPU, 96GB RAM). In real-world usage, I’d expect the gap to be minimal unless you’re pushing the system to its absolute limits.
Many people assume the M4 is simply a generation ahead of the M3, but Apple seems to be treating them more like parallel tiers with different enhancements. In the long run—whether M3 or M4—both will be slow/obsolete in 5 to 8 years anyway.