OK, I'm going to jump in for a bit here. A lot of folks focus on bridges as magical things that can add sustain and the like. Technically, yes, they can, but.....
When a string is vibrating, there are waves traveling up and down the string. When one of those waves hits one of the ends of the string, most of the energy is reflected off that end and goes the other way. The bit that is lost is indeed part of what reduces sustain (there are air losses, and losses in the string too).
A lot of time around here I see people talk about a bridge coupling vibrations or energy into the body. This is nonsense - if you "couple energy into the body" really well, that energy leaves the string, and you get no sustain at all. What you want (assuming you want sustain) is for both ends of the string to NOT steal any energy from the vibrating string - you want both ends to be masive and stiff, so the energy reflects off the end and stays in the string.
Next point: We've got a string with 2 ends. If we want sustain, we want the ends to be massive and stiff. One end involves a decent sized chunk of metal (often with hundreds of grams of mass) bolted to a chunk of wood that weighs a few pounds. The other end has a small piece of metal (a gram or two maybe? - I've never actually weighed a fret), attached to a much thinner piece of wood. Given that discrepancy, the neck end of the string is going to have more loss of energy than the bridge. If sustain is you goal, which end do you work on - the one that doesn't lose much energy, or the one that loses most of it?
If you've ever had a bass with a bad dead spot, you know how much sustain a bad neck end condition can steal. All the weight in the world at the bridge end won't fix the typical dead spot - the problem is elesewhere.
OK, but what about tone? Well, tone (at least the part of tone you can affect by changing end conditions) is very related to sustain - if you leave all the energy in the string, it'll have a particular sound; what you take out is what'll give you a different sound. The most obvious example of a tonal difference from changing an end condition is...a fretless with a hard board. Mwah is simething you don't get on a fretted bass, you get it on a fretless because....one end condition has changed.
A bridge can add sustain or change your tone , but not as much as you might think - any improvement at that end of the string is pretty limited, given that the problem is elsewhere. I have owned a couple of basses with incredible sustain - enough that learning how to damp a string was a critical skill. What separated those basses from nomral ones? Metal necks - mass and stiffness galore on the end of the string that needs help.
So, we've got a buy with a "better" bridge - at least he thinks so, and is passionate about his design (I actually like that). Given what I know about how bridges work, the things I care about are things like do the saddles stay in place, is it low enough mass that it doesn't make my bass a boat anchor, does it start the string at a place where I don't wind the fat part around the tuner post, etc.
And yes, I'm not a fan of having the fatter part near the ball end as part of the vibrating string - in college we did an experiment where we half unwound a string - we chaged the mass distribution of the stringto where it wwasn't uniform along its length. The harmonics of that string were nowehere near multiples of the fundamental - the thing sounded horribly out of tune with itself. Granted, that's a more extreme example than what's happening here, but the principle is the same - its not a simple "intonation error" that that causes, it's something you can't actually compensate for - the harmonics are not right, no matter where you locate the bridge saddle. Wil you hear it? Maybe not, but it'd bug me knowing it was there.