They actually HAVE to be hot to function normally. If a warm trans tunnel becomes too much of a worry for some, another option would be to wrap the converters with high-temp exhaust wrap. It will lower the temps underneath the trans tunnel, and on the drivers' side, have the added benefit of lowering the operational environment near the trans-selector switch which has proven to be another issue with VX's.
Incidentally, transmissions also require the trans fluid to run at high temps to operate correctly. The main reason trans coolers are suggested is when a particular vehicle is going to be used for towing. In those instances, the trans fluid will be heated too much, and an external/aftermarket trans cooler reduces temps back down to normal. A trans cooler installed and run under normal driving conditions won't necessarily hurt anything, but it will cause the trans fluid to take longer to get up to normal operating temps (especially in colder weather), so trans shifting tendencies will be affected until adequate temps are reached.