Everend, it is critical that your router is centered on a mounting pate or with its sub base plate for use with guide bushings. If you are using a large diameter bit having the plate centered can make the difference between chewing an off center hole and just fitting through. Even for those who are not currently using guide bushings it makes sense to set up so you can in the future. If you are doing inlay work you need your sub base plate centered so your cuts are accurate. Centering kits and cones are under $10 and I feel this is money well spent.
If your router uses slotted screws to attach the sub base pate I highly recommend that you change them to Phillips, Allen or Robertson(square drive) screws; this will save you from problems down the road.
"Living in the D" (this means Detroit!)
"It's fine to disagree with other members as long as you respect their opinions"