My take on deleting is that if emissions equipment was actually reliable then less people would be interested in deleting. Calibrated Power has proven you can make good power with emissions intact, but the equipment just is not as reliable as the rest of the truck.
On my 06 the only real issue I ever had was EGR related, and that's a 14 year old truck so I don't have to deal with DEF or DPF.
06 LBZ CCSB
With some stuff.