I've replaced the string and bus string on my '96 Mathews Ultralight every year since i've owned it. it's now 6 years old and still shooting as well as the day I bought it. It cost me $65 bucks to replace them every year, I figure thats cheap insurance to keep my bow from blowing up on me because the string is streched to far. Plus the string system is the starting point when tuning your bow, if it's streched to far everything else will be that much harder to tune correctly (or it really won't be in tune because of the string).