You're correct that these brands share the same parent company (Husqvarna Group), which leads to some technological overlap. For home users with a €1000 budget:

Husqvarna typically offers:
Premium build quality and durability
More advanced navigation systems
Better handling of complex lawns
More comprehensive app features
Higher-end customer support

Gardena generally provides:
Good balance of features and value
User-friendly interface
Reliable performance in medium-complexity lawns
Slightly more affordable than equivalent Husqvarna models
Appealing design aesthetics

Flymo tends to be:
The most budget-friendly option
Simpler in features and capabilities
Better suited for smaller, less complex lawns
Less advanced in navigation technology
Good for first-time robot mower users

Two-Disc vs. Single-Disc Robot Mowers
Two-disc mowing systems offer several advantages:

Potential benefits:
Wider cutting width, potentially reducing mowing time
Better coverage efficiency in a single pass
Potentially improved handling of different grass types
May handle edges better in some yard configurations

Potential drawbacks:
Added mechanical complexity could mean more points of failure
Potentially higher repair costs
Will consume more battery power
Could be less manoeuvrable in tight spaces

For most home users, single-disc systems have proven reliable and effective. The two-disc technology might be most beneficial for larger properties or those with varying terrain types. If you have a standard residential lawn without unusual challenges, the added complexity of a two-disc system might not justify the potential benefits.

If we compare the Luba 2 AWD (Two-Disc System) with the Luba Mini (Single-Disc System) -
The two-disc Luba 2 AWD makes sense for larger properties with varying terrain, while the single-disc Luba Mini is more practical for standard suburban plots with simpler layouts. The Luba 2's dual-disc system isn't just about coverage speed—it works in concert with the AWD (All Wheel Drive) system to manage difficult terrain that would challenge most robot mowers.

For average home users, the decision between these models should primarily be based on garden size and terrain complexity rather than focusing exclusively on the number of cutting discs. The Mini's single-disc design is perfectly adequate for the smaller gardens/lawns it's designed to handle.

Thanks
Mark