2025 Grand Design Solitude 345GK vs 2025 Keystone Montana 3531RE

Detailed Comparison

Head to head, the 2025 Grand Design Solitude 345GK and the 2025 Keystone Montana 3531RE each bring unique strengths to the table. Which one deserves a spot in your driveway?

Dimensionally, you're looking at 37.0 ft for the Grand Design Solitude 345GK and 35.5 ft for the Keystone Montana 3531RE. The Keystone Montana 3531RE carries an extra 2,700 lbs, which affects tow vehicle requirements and fuel economy.

For sleeping arrangements, the Grand Design Solitude 345GK offers room for 4 and the Keystone Montana 3531RE can handle 6. The Keystone Montana 3531RE benefits from 3 slide-out(s), expanding the interior when parked.

Looking at self-sufficiency, the Grand Design Solitude 345GK packs 56 gal of fresh water and 200W of solar. The Keystone Montana 3531RE counters with 96 gal fresh water and 250W solar.

Price is often the deciding factor. The Grand Design Solitude 345GK starts at $162,000 MSRP, while the Keystone Montana 3531RE commands $165,000 — a $3,000 gap.

Families with kids will appreciate the extra sleeping capacity and living space. Off-grid campers should pay close attention to solar wattage, battery capacity, and tank sizes. Full-timers should prioritize tank capacity, storage, and overall living comfort.

Whichever you choose, you'll be getting a capable rig. Just make sure to inspect one in person before signing.