Application is for a '00 Mitsubishi Montero. Previously, I used Motorcraft Premium Green coolant and used to drain the radiator first, remove the top radiator hose, and add distilled water until it ran clean. Then I would dump in a gallon of MC PG coolant and be done. However, Motorcraft has gone up in price by a ridiculous rate and it's put me off. What I used to buy for $8.25 a gallon is now $19.80. As it's a conventional coolant, I'm considering alternatives. Prestone all-makes pre-mixed green coolant seems like a quality choice. The other is Mitsubishi's own pre-mixed coolant with a 30% concentration. Both are conventional. Because of local climate conditions (dust, etc.) I flush my coolant every 30,000 miles. Should I just go for the cheapest option in this case? I replace my cap every time I flush the system. Every second change, the thermostat and hoses are replaced too (which is what I'll be doing this time round). Thanks!