I hear amazing things about them and in videos/live shows.
Sometimes I feel like a more value-oriented line (Epiphone, Squier, etc.) will offer a quality instrument that makes you want to stay in their brand, but move up to a Gibson, Fender, etc. when the time is right. I haven't gotten that with the non EBMM versions of basses I've tried by them. I really feel like this isn't the typical case, as I read about many enjoying their Sterlings and non-EBMM variants. I've enjoyed the tones people get with them too.
That isn't to say I don't still want to try a proper EBMM, or that I won't enjoy the Sterling Bongo I have now. I have my gripes, but I've since set the bass up for Drop C tuning. It's honestly doing pretty well there, and I'm excited to try some MEC passives in it. I feel ok "modding" this bass, but likely wouldn't with a true EBMM
For the neck shape, what would you say is different? I've read a bit about the differences in pickups and hardware, but haven't looked into the neck yet. I watched a video about John Myung's signature bass and how it's a 6 string with a 5 string nut. I prefer a less-wide nut/tight-string spacing with a thick neck. If I ever do a custom bass build, I'm either going to make the builder uncomfortable or excited about the ridiculous neck dimensions I want on a 4 string bass.