Pretty much all the Holley carbs have gaskets below fuel level and it is an imminently successful line of cabs. Many carbs have side hung floats, including all of the 1850 4 BBL Holley carbs which have been great for about 50 years now! And many carbs suffer from bad accel pump diaphragms. The Carter BBS has issues with worn out shaft bushings, so add that to you list of carb deficiencies. None of these items are 'inherently' bad as they are common to many carbs.