I find my entire network much more well behaved if I minimize the reboots, power switches, etc. on everything. My WD Player is located in a relatively cool location and has a My Passport drive attached. What is the risk of leaving this on, pretty much all the time?
Other than it wasting a small amount of electricity, there is really no risk in leaving it on. Some of us with power up issues, such as the box powering on at a resolution that the TV does not support, leave it on to avoid having to deal with the firmware problems.