50 mm 1/4 vs 1/8. Which is better for a beginner as first lens?

I have a canon rebel xs, currently I only have the 18-55 mm kit lens. I am looking for an upgrade. I want something that will make my images sharper, and provide a more blurred background or bokeh. I have been looking at the f1/4 and f1/8. This is my first lens, and I am looking for something that will provide me with a lot more than my kit lens can. I know a lot of people that have bought the 1/8 50mm and then around a year later upgraded to the f1/4 because they realized what they are missing. Do you think this is a good idea to buy this as my first lens?