I'll make some general comments from my study over these past few years. I wasn't at Thiel during the transition to China, but have learned some from first hand operatives. Here on this form there was surprise and disappointment that their Thiels weren't wholly "made in USA". I shared that surprise. In my time we made everything - unusually vertically integrated for a small company, using best of form american and european parts. We also valued affordability - we wanted our products to be affordable to folks like us. Those elements contain conflict, especially as the world marketplace gravitated toward lower cost elements from far-away places. As time went on, increasingly greater part count could no longer be sourced in the USA. Add to that fact, Jim had cancer for at least 5 years before his 2009 death. During that period the company outsourced more and more to simplify its operations to attract a potential buyer to carry on the company.
Evidence shows that during that time outsourcing crossovers went to China, and it also went to lower-spec components. Rob says that Jim tested and approved all changes and Kathy's marketing opinion was that performance wasn't degraded to affect the market niche. But nonetheless downgrades were brought into the mix.
For example, the 2.4 original specs include all polypropylene caps with polystyrene bypasses, built on point to point masonite boards. Beetlemania's SEs were late production FST/China with sloppy coils, polyester caps, PP bypasses on glass boards - definitely a notch or two down. He has shared in these pages the summary of his detailed, painstaking and thorough upgrade and the sonic outcomes. I have evaluated his FST boards and judge them to be inferior to classic Thiel. They include solutions we superseded in the late 70s with the model 03. It looks like Marqmike's boards are transitional between Lex and FST. MM's caps are Chinese production when Solen (France/Canada) took their bulk production to China. The coils are decent, probably from ERSE production moved to China. Audiophiles consider masonite point to point superior to 'glass. Note these glass boards are a hybrid with point to point layout but with copper solder pads for terminals. That's a step down from Thiel's physical twist joint stabilized with solder. The coil and hookup wire are CDA102, a step down from best of form CDA101, but still above the normal CDA110. I judge that these downgrades taken collectively, audibly reduce transparency and precision, but not by a lot.
I now have a pair of 2.4s of similar vintage and style as Marqmike's. I can't afford the time, but would be interested to hear a comparison of this execution vs original blueprinted Thiel execution. I clearly project the winner, but I don't know the particulars.
Beetle's execution takes original performance to another league. I have since gained access to a yet further refinement of the ClarityCap CSAs. The CSA is a game-changer to me, using foamed copper rather than zinc for the capacitor end caps. The subsequent Purity Cap increases the CSA copper cap thickness from 1mm to 10mm for significantly further enhancement, especially in high power usage. Presently I'm coaching a 2.4 upgrade which is likely to include CSA vs Purity comparisons for your and my edification.
My hotrod garage is presently closed, looking for a new location; but the project is alive and well with advancements being made on multiple fronts. One of these days we hope to offer various plans or kits or services to upgrade your 2.4s etc. to the limits of your budgetary courage. Meanwhile there are available known upgrades with no down-side risk.