If you like today's McIntosh, there's a good chance you'll like vintage McIntosh. If you cannot audition the Mac sound from the days of tubes, what Mac produces today (solid state or tubed) is quite the same as the sound they had forty years ago. Listen before you buy to determine whether you like the McIntosh sound. This won't please everyone today and IMO it won't mate well with some of today's more 'hifi-ish' sounding components. The Mac house sound is big and dynamic with a penchant for staying true to the signal. McIntosh sound is quite identifiable to those familiar with live music and the general approach American designers took toward their craft. You'll have to decide what you think about McIntosh circuit quality but most people with the money to spend in the tube years felt they had few alternatives. Mac strove for the highest reliability possible in those days - not to say they still don't - and this means their switches and controls were of the sealed variety and thus had fewer problems with oxidation and aging. During this same time frame, many other manufacturers would of course use much higher toleranced parts in their high end gear.

For the most part those tolerances would be considered tight quality control for many of today's manufacturers. 10% capacitors exist in most locations in a Mac product from that same time period. 1% resistors are not uncommon in a Mac component from the 1950-60's tube era. Most of the passive components such as resistors and capacitors were spec'd to much tighter tolerances than the all but a tiny portion of the competition cared to use. One factor that set the McIntosh's apart from most other lines was Mac's attention to detail. The McIntosh pre amps were considered among the finest made by any American manufactuer in the days when tubes ruled. If you allow me to stay within the McIntosh line, I can give more pertinent answers. Your questions are really too broad to answer when you ask to compare the output of the entire industry at any one point in time.

Mcintosh unity coupled transformer