Xperience is a great rapper. He's definitely a part of Seattle's massive Oldominion collective, which is in many ways the core of Seattle hip-hop as an entity. I'm not sure when he started - I could be very ignorant - but I first became aware of him from two local Seattle projects - an Oldominion album called The Gigantics and an entire album that Xperience recorded with Grayskul called Facefeeder.
Xp (I hope he likes that nickname) did indeed pay off with his grind. Grayskul is fairly well known but Xp is now being featured on Macklemore's albums. His potential is very high - I think his new project Th3rdz could certainly be the start of something spectacular.