IIMHO the Sean case primarily targets the Super Franken builders (gen or clone 3135 mvt, gen dial, hands, crystal, crown, tube etc.)
If you're not planning to use a clone or gen 3135, gen dial and hands I think you'll do better cost-wise sticking to a TC and adding gen crystal and insert
And yes....gen crystals and inserts make a huge difference and are well worth the cost and the trouble.