The difference between the YUKA Mini 500 and 600 models is purely software feature on how much the mower is designed to mow in terms of square meterage. Both models share identical hardware specifications, motors, and physical components - the distinction lies in the software-limited coverage area, with the 600 model being programmed to handle up to 600 square meters while the 500 is capped at 500 square meters. This software-based limitation is a common approach manufacturers use to create product tiers without actually changing the physical product.

You would be always better going for the largest you can afford to reduce the number of charge cycles needed to mow your lawn to preserve the life of the battery. Even if your lawn is smaller than 500 square meters, the 600 model would complete the job with fewer charging interruptions. Remember these batteries in the YUKA Mini can now be easily replaced by the user (not the case with other brands), which is a significant advantage for long-term ownership. While the £50 price difference might seem tempting to save with the 500 model from Amazon, the extra capacity of the 600 model from Mammotion (especially with their £50 voucher making them similarly priced) would likely provide better value over the life of the product.

Depending on how large your lawn is, you may even want to consider pushing to the 700 for the 4.5Ah battery.

https://easylawnmowing.co.uk/mammotion-yuka-mini-review/

Hope this helps
Mark