At 690 V AC, the rating drops to 2 kA, so verify your line voltage against the table before specifying. The gG fuse coordination values are given: 63 A at 400 V, 50 A at 500 V, 40 A at 690 V — these tell you the maximum upstream fuse that maintains selectivity. The maximum switching rate is 15 operations per hour at AC-3 duty (cites:,). For a transformer that cycles on load, that's ample; for a high-speed process with frequent starts, check the duty cycle.
Screw and snap-on both work; the snap-on saves time on a panel build. Clearance requirements: 50 mm upwards and downwards, 30 mm at the sides, 0 mm forwards and backwards. That means you can butt it against the back panel and adjacent devices, but leave breathing space top and bottom for arc extinguishing.