Case XT Series vs 400 Series- ATTN KSSS

What is the difference between these two series- I am looking at the 90/95, 450/465 end of things. Body types seem identical between the radial-vertical models as far as I can tell, but what is the preferable of the two engines-hydraulic set-ups? I see a lot of love for the older Case stuff, (4-390 engine and the 1845c especially), but the consensus seems to be that they get worse with each new series that comes out.

Case XT Series vs 400 Series- ATTN KSSS