I bought the 17543 and some Sears router bits. I thought the router bits could be used out-of-the-box with the 17543. However, I found that the router bits, if used will damage the plastic sub-base plate because the hole diameter is too small for the router bits. I found that Sears offers a set of five or six sub-base combos, one set for the fixed base and one set for the plunge base at a price of $19.99. A bit of a rip-off. I had an old Sears router at one time and I don't recall that it had a plastic sub-base mounting plate and it worked fine for free hand edging. Do you really need to use these plastic sub-base mounting plates or for that matter the plastic sub-base mounting plates that came with the 17543? Another comment is that the router seems O.K. (sub-base problem not withstanding) but the manual sucks. The description of the router height adjustments and zeroing borders on cryptic--very poorly written.:angry: