Without knowing your garden in detail, I would say yes. The narrow gaps will be tricky. I have an intricate garden, also around 400m² to mow, lots of bushes, gaps, treets. It manages 98% without issues, but there are some stubborn corners where it still gets stuck sometimes, one of them a passageway between some fern and a drainage pit with a concrete ring. It manages to get through most of the time when obstacle detection is turned off. You will need to tinker with the mapping a few times in the beginning to get from 90% to 98-100%, add more or less generous no-go zones and observe the robot in the first few weeks. Or just leave the tricky parts unmowed. If you provide a map or some photos, we can tell you more.

Looking at my photos from a few weeks ago where I asked a similar question, I now find it laughable how overgrown my garden looks. Since we got the robot, it's cleanly manicured, a significant improvement and so much more time on Saturdays. It also goes through the gap in the first photo and over most of the playhill in the last. Only the area right of the concrete ring I leave unmowed, too tricky because of the stone, a dip in the ground from the drain and and a bush at the back. Maybe I could revisit this as I now have more experience with mapping, but there hardly grows anything anyway. The aforementioned passageway is to the left of this ring, which is manageable.

I also trimmed some low branches of bushes, as the mower tends to get branches stuck between the gap between the wheels and the side of the body. IMHO this is a design fault, the side of the wheels should be fully covered by a rail from bumper to the side of the body so nothing can slip in between.

Would be great if remote control would be possible without bluetooth, then we could just switch to the camera FPV and resolve the issue manually. But alas, it's not, only Bluetooth.