I bought two of these Kitty Sill Carpet Perches for my three cats.  One for each front window in the living room and they just love them.  My female cat loves to hang out in there by herself and my other two male cats use them occasionally.  The largest of the three weighs almost 20 pounds and the perch holds him up just fine.  I have had them installed for about 8 months and so far no problems.