I have all of the Festool sanders being discussed above and several other brands and types, too. I am also an amateur/hobbyist DIYer. I bought my RO 125 and ETS 125, Deltex 93, and LS 130 before I won an ETS 150/3. I did so because at the times of those earlier purchases most of my projects involved sanding old wooden trim around the doors, windows and baseboards of my house, and the doors themselves. So smaller, lighter sanders were preferred. But when working in my shop making furniture, the ETS 150/3 has become my "go to" sander for most projects, unless its size is simply too large to fit. I especially like the ETS sanders for flush sanding stiles/rails joints of cabinet doors. The ETS 150/3 with a hard sanding pad excels at getting such joints flush without gouging or rounding off the edges. You can do this work faster with an RO sander in its Rotex mode, but it requires a careful experience hand to avoid carving away more than you intended. The LS 130 has become my second most used "go to" sander because its linear action and variety of pads allow it to be used for a wide variety of delicate operations, e.g when you are flush sanding a strip of hardwood edging glued on to commercial veneered plywood where being overly aggressive will quickly cut through the veneer which is often much less than 1/40 inch thickness in the sanded plywood as delivered. The RO 125 sees more duty polishing and waxing my cars than in woodworking, unless I need to hog off some wood, but not so much as to pull out my old Bosch 4" x 24" belt sander which is far more aggressive, but also far harder to control.
In sum, I agree with Daviddubya, unless you think you will never buy another sander, in which case I recommend an RO 125 or RO 150. The latter is more veersatile because a wider range of supplies and accessories are offered for it. But I bet you cannot buy just one; you'll eventually want another better suited to the work you plan to do.
Dave R.
