Power flush is not bad, but if you change your fluid on a regular basis like every year then you shouldn't need a power flush. A power flush sometimes stirs up the loose metal shavings within the tranny and causes harsh shifts for alittle while till they settle back to the bottom. There is a DIY tranny flush on here or somewhere. For an 05, just change the fluid regularly and maybe 5 to 10 years down the raod you can think about a power flush.