2024 Keystone Montana 3121RL vs 2025 Keystone Montana High Country 331RL

Detailed Comparison

Two popular options on many shoppers' shortlists — the 2024 Keystone Montana 3121RL and the 2025 Keystone Montana High Country 331RL. Let's see how they compare across the specs that matter most.

The Keystone Montana 3121RL measures 28.0 ft in length at 12,000 lbs, compared to the Keystone Montana High Country 331RL's 36.0 ft and 15,900 lbs. GVWR ratings sit at 16,100 lbs and 18,200 lbs respectively.

The Keystone Montana 3121RL sleeps 5 while the Keystone Montana High Country 331RL accommodates 6. Slide-outs play a role in livability: the Keystone Montana 3121RL has 1 and the Keystone Montana High Country 331RL has 2.

For boondocking enthusiasts, tank sizes matter. Fresh water capacity goes to the Keystone Montana 3121RL at 93 gallons versus 82 gallons. Solar-wise, you get 200W on the Keystone Montana 3121RL and 300W on the Keystone Montana High Country 331RL. Battery banks are 200 Ah and 350 Ah.

At $66,000 MSRP for the Keystone Montana 3121RL and $50,000 for the Keystone Montana High Country 331RL, the Keystone Montana High Country 331RL saves you $16,000.

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.

No comparison can replace walking through each unit yourself. Visit a dealer and experience the layouts firsthand.