A good GPS running watch tracks your miles, maps your routes, and keeps your heart rate in check so you do not burn out. You want to buy one that lasts for years rather than replacing a cheap model next season.
Spring is the best time to buy because new models drop and retailers slash prices on last year's version. You get the exact same durability and mapping tools for a lot less cash.
Remember that the 0% intro APR for 15 months on purchases and balance transfers is a deadline, not free money. If you still have a balance left when those 15 months are up, interest will kick in on what is left.