Wire bond packages are generally more cost-effective and thus found on the low-cost Xilinx devices. The packages are durable, but from a thermal perspective, are not the highest performing and thus not recommended for high-power and/or high ambient environment operation. The IC is often encapsulated in a plastic mold which can impact the thermal resistance to the case. This is fine for lower power operation, but could pose challenges in higher power and higher operating temperature environments.
Figure 1. Cross Section of Wire Bond Package