Trunk comparison: BMW X5 vs Opel Astra Wagon

Key Differences
When comparing cargo capacities, three differences stand out: With all seats folded down, the cargo floor of the BMW X5 is 7.9 in (12%) longer than in the Opel Astra Wagon.
The depth of the trunk (distance from loading edge → trunk floor) is 0.4 in (100%) greater in the Opel Astra Wagon than in the BMW X5. Additionally, the loading edge of the BMW X5 is 7.9 in (34%) higher above the road than that of the Opel Astra Wagon.
All other deviations (trunk length with front seats upright +1.2 in/3%, trunk opening height +0.8 in/3%, width differences 1–1.6 in or 1–4%) are minor and hardly noticeable in practice.
Impact on Usability
Due to the 12% longer cargo area with folded seats, the BMW X5 is better suited for long or bulky items (e.g., slats, long furniture parts, skis).
However, the significantly higher loading edge of the X5 (by 34%) makes lifting heavy loads into the trunk more demanding and ergonomically less favorable; those who frequently load heavy items benefit from the much lower loading point of the Astra Wagon.
The slightly greater trunk depth measurement in the Astra (+0.4 in/100%) means that the floor area directly behind the loading edge is slightly lowered, which makes placing flat items or stacking in the front area a bit easier.
Overall: the BMW X5 offers more length for long cargo with folded seats; the Opel Astra Wagon is ergonomically better for daily loading and unloading and for heavy or frequent use near the loading edge.