The Spisser Landstraße is the main route up to Samnaun. Predominantly in Austria it does come to the Swiss Border near Samnaun. On the whole the road is a joy to ride with a good surface. Samnaun is a duty free area and Petrol is cheaper than in Austria. Unfortunately some people overfill their tanks and deposit any savings they have made on the road surface under braking on the way down so you have to be aware. The attached video is as bad as I have ever seen it. Also being Duty Free and in Switzerland, Duty Free allowances apply as you enter Austria as Switzerland is not in the EU. Often the Border Crossing is unmanned but that doesn´t mean you are safe as there are frequent mobile custom checks further down the mountain so don´t be tempted to overdo the cigarettes.