I have had very good experience with Shuguang tubes. I am using eight Shuguang 300BS tubes in my VAC amp. The tubes come in pairs, in a very sturdy black cardboard box. They are encased in foam. They are the globe shape, not coke bottle. There is also a white paper with test measurements. I think they sound great. Make sure you get them from a dealer with a good return policy. 300B tubes can be very volatile. In my experience, usually the first one hundred hours are the most critical.
My amp likes them very much. they are very smooth , detailed, dynamic, wide open and have a wonderful presence. I have had a couple fail early on but my dealer promptly exchanged them. I think it is always good to have spare tubes on hand for backup. I keep spares for every type of tube I use in both my anp and preamp.
