I agree with most of the others... I would not be spending money to get status when I am so far short.... especially this early in the year.
What travel do you anticipate in 2015 that would give you substantial value for the money you spend now?
If you are willing to do this, why not take trips to make it mini-vacations instead of just giving the money to SPG?
If it was 4-5 nights, I could see doing it and giving the money now for something in the future.. but no way for the scenario you describe.