Quality Would you consider this product to be made well? How dependable? The highest quality available. Comparable to Old school American Made tubes. Reliability How has it stood up over time? These are pretty new. If they last half as long as the originals you may never have to change your tubes, because the originals are still running (50 years later) Overall Your general opinion of this product. When it was developed in late 50's The 6550 tube was the American Version of the British KT88. Both tubes represented the apex of vacuum tube technology development. There was litterally, never a better tube made. The Tung Sol 6550 was a millitary/aerospace grade tube that was in every way the American equal to the British made, MOV - KT88 that produced MOV and "Genlex Gold Lion" KT88's..This Tung Sol RI 6550 is, physically,and electrically about a 98% accurate copy of the original. The entire "Tung Sol" branded product line from New Sensor(called sovtek by many even though sovtek is only one of the brands they manufacture) is head and shoulders above all competition, equalled in quality and performance only by New Sensors other brands.New Sensor is BTW,a privately owned and wholly American company Playability and Feel How does it feel, Heavy, Fast, Chunky? How was the neck? Are the controls easy to get to while playing? Tone Bright and snappy? Dark and smooth? Were the pickups hot, mellow, thick, thin? AS Described in SOUND. The Best. Finish How did the stain or paint job look? I think it looks awesome. The bottles are so cool they should probably be on display. Use them in a Jolida. Action How was the action out of the box?