Hey Terry, For me the 50/50 mix is way cheaper. That is the main reason I made the change a few years ago. But one important advantage is the mix drys a lot faster. I used to wait up to a week for Danish oil to dry before I applied my topcoat. With the mix, I can apply my topcoat the next day.
Now, if you buy a quart of Danish oil verses a gallon of boiled linseed oil and a gallon of mineral spirits, the price difference is substantial.