If you have a brand-new design, you might consider CY2305C or CY23EP05. The EP part has better performance. The C part is a meant to be backward compatible with CY2305, but it is a new design and different process technology (more advanced).
CY2305C is the same device as that of CY2305 in form, fit and function with the only change in the process technology. So it is a die replacement part for the CY2305. These "C" based devices are cost-reduction versions meant to replace the CY2305. It is a 3.3V part.
CY23EP05 also is a newer technology part which has low jitter and supports both 2.5V and 3.3V operation. CY2305 and CY2305C are 3.3V-only parts. The devices are otherwise the same in terms of form, fit and function. CY23EP05 is an enhanced performance version of the CY2305 and CY2305C devices and therefore costs more.