Pass a bug around until it goes away. Prove that the customer does not need a bug fixed. Have customers prioritize a list of bugs. With luck, customers will make the mistake of marking some of the bugs as anything but critical. When all else fails, attempt to fix a bug within 2-3 revs.
Beta testing makes users feel good, but does nothing for quality.
Quality is a result of design, not testing. The lowliest human is better at adapting and making decisions than the best computer program. The only exception is when a human is following government regulations. Updating any software will require you to update all software. This is detailed in the 'Continual Purchase' clause of all Software contracts.