I'd definitely recommend speaking to Jon. Like I said it worked out basically the same price as a similarly spec'd Warmoth guitar neck. The only downside really was the wait.
I've just finished a build with all gotoh hardware including elephant ear resolites. Really impressed with them. They're stable, feel great and obviously are ridiculously light.
Here's a photo of them in situ.
Fair enough, assuming it's the same result through both that's my hypothesis disproven.
Could it be a dodgy string or pickup?
*edit* or something set up related?
Lovely looking bass that.
Regardless of whether or not it's a "true" grabber it's a ultimately a tried and true combination of parts and design. The main thing is that it does what you want it to do.