yamaha ox66 O2 sensor

I have a 1999 Yamaha vmax 225 ox66. I was told I have a bad O2 sensor and was seeing if anyone has ever replaced theirs with one besides OEM. I really don't want to have to spend $300 on one and have read many places where people have replaced it with an NTK 21006 O2 sensor made by NGK for only around $40.