Sgbwill2 sums it up very nicely with the ease of modification and/or parts replacement.
The clean point to point internals was one of the attractive features of this amp which made me buy it. In all the reviews I have read the internals and build quality have been highly praised and allows for easy modification / replacement of parts :). I am also led to believe the La Figaro 339 is in the same league as the WA2 at almost half the price, and going by the headfonia review the reviewer actually prefers the warmer sound of the La Figaro. Cant wait to try it I'm so excited :D should be a nice upgrade from the LD.
I could very easily get used to the 339 if it is anything like Lieven's review.
OTL Amp comparisons
Compared to the Bottlehead Crack, the OTL Crack is the faster amp of the two, it it clearer sounding and focuses more on the treble. Bass with the Crack is punchier but not as deep and it doesn’t quite have the same rumble. Overall the 339 is smoother, warmer and laid back with an even bigger sound stage. It just makes you feel the music better (softer) as the crack. The Crack is a great deal and an excellent amp as we already said in our review but the La Figaro 339 is the better amp for me. Compared to the Woo Audio 2, the 339 is the more tube-ish sounding amplifier with a much warmer sound. The WA2 sounds much cleaner and faster but misses the warmth and soul I like of the 339. The WA2 is more analytical as the 339 and the bass depth and rumble isn’t quite the same, however it does have an even bigger sound stage.
Now you have different tubes to chase...