Very sturdy chairs.  I opted for the wooden base over the vinyl (durability vs. comfort).  This style is my new favorite over traditional wooden chairs.  Wooden ones always have issues with separator dowel and legs coming apart over time (from people unsuccessfully "hop sliding" the chair on carpeting to adjust their positions).  If it gets too uncomfortable, I can always add a set of washable cotton chair cushions.  The seat is not attached and (as others have noted) does not have pilot holes, so connection to the metal base should not be attempted with just a manual screwdriver.  Use an electric driver, but be careful not to overdo it and strip the screws -- they're short with wide threads.  I used a quick shot with a cordless drill using a Phillips bit.  A quick zip, they bite into the wood easily, and the screws are attached.  Nice chairs.  Easy assembly.