Yamaha DTXpress/DTXplorer/DTXtreme

My son has a DTXPRESS 1 that has a staticy cymbal, I pretty sure the 
sensor is wearing out not a problem with cables or connections. I do 
not know if this is fixable but I am willing to order a replacement as 
he is pretty serious as a drummer. But as long as I am ordering a 
replacement is there an optimal "upgrade" cymbal that will work with 
the first generation DTXpress? If there is a simple sensor fix please 
let me know I'm not a drummer or musician but comfortable with 
electronics.