+1 to much of the above. I have had dealings with both firms. In my limited experience, both are working hard to serve their customers to the best of their ability. For me, it is also something of a choice between the culture of both firms, based on their stakeholders' experience and training; the instruments are, IMHO, expressions of that. So, I got a taste of both company's cultures, as part of my decision. For me, it was also partly about my perception of their firms' "fit" with my ideas and hopes.
The products, visions, levels of experience, and processes are different. Having had some dealings with both companies, and being in the process of having a La Scala built, now, I can only say that, IMHO, there is no substitute for visiting the shops, personally, playing actual instruments, talking (offline) with luthiers, and asking other bassists (whose experience and playing one finds relevant) about their candid assessments.
The Internet is amazing. At 49, I am still blown away by what we can see and hear, with a couple of clicks. But, obviously, its not Internet "vs" physical reality; in my recent selection process, I have mixed online chat and information gathering with plain old driving around, sawing and thumping on basses, listening to folks, and noting how they handle themselves, on the phone, at the computer, in the workshop, and face-to-face.
Ultimately, for me, it mostly comes down to practice and playing time, developing my musical mind, carefully strengthening muscular memory, and playing concepts. I can still play pretty poorly on the nicest bass; I have proved it! I know that one thing that will make me play better on my La Scala than I did on my Upton Professor is if I can spend more time with it.
