I've been very satisfied with the CX2510 cab. Can a CK2620SE do more? It sure can, but that isn't the size of tractor I needed. I needed a CS2520, Kubota BX2680, or JD 1025R sub-compact size machine by the numbers. I really wanted a cab which would add cost to those purchases. I looked at bigger machines based on advice to always buy a size larger than you need. The CK was too tall for my garage door (had ag tires, R14 may have fit) and too wide (rear tires) for the wooded trails I'm maintaining. I've been on both machines and the CK does feel a larger all around. The CX was right in the middle and the very capable for cost with the most standard features in that class CX2510, B2601 (no factory cab), 2025R (no ac).
The CX has done great with 54" and 55" attachments. It has dug, moved many pallets, moved large rocks and cut tree sections with a grapple, been a wheelbarrow for buckets filled with sand and flagstone, leveled trails and sled lanes with a box blade. Rear tires are filled with rimguard. The power level between the CK and CX is the same for ground engaging or pto work. I'm always fine with low on the transmission for my use case. High is underpowered for both unless you turn up the up the fuel screw and advance injection timing to be similar to the old CK35 engine configuration. Its really just for moving around unloaded faster.
The CK was overkill for me too. The CX was a huge upgrade over the CS. Buy what fits your need and what you can accommodate at your property.