2025 Newmar London Aire 4551 vs 2024 Entegra Cornerstone 45X

Detailed Comparison

Both the 2025 Newmar London Aire 4551 and the 2024 Entegra Cornerstone 45X have loyal followings, and for good reason. Here's an objective look at how they measure up.

Starting with size, the Newmar London Aire 4551 measures 35.5 ft long and tips the scales at 17,700 lbs dry weight. The Entegra Cornerstone 45X comes in at 28.0 ft with a dry weight of 21,800 lbs. That gives the Newmar London Aire 4551 roughly 7.5 extra feet of length.

The Newmar London Aire 4551 sleeps 4 while the Entegra Cornerstone 45X accommodates 6. Slide-outs play a role in livability: the Newmar London Aire 4551 has 4 and the Entegra Cornerstone 45X has 3.

For boondocking enthusiasts, tank sizes matter. Fresh water capacity goes to the Entegra Cornerstone 45X at 114 gallons versus 73 gallons. Solar-wise, you get 200W on the Newmar London Aire 4551 and 450W on the Entegra Cornerstone 45X. Battery banks are 250 Ah and 350 Ah.

At $359,000 MSRP for the Newmar London Aire 4551 and $362,000 for the Entegra Cornerstone 45X, the Newmar London Aire 4551 saves you $3,000. With only a 1% price difference, the choice comes down to features rather than cost.

If you're traveling with a family, look for the model with more sleeping positions and better storage. Boondockers: look at the fresh water capacity and solar/battery systems — they determine how long you can stay out. For the full-time RV lifestyle, every gallon of tank capacity and every inch of counter space counts.

Ultimately, both rigs have their merits — test drive each one and see which floor plan speaks to your lifestyle.