I'm lucky enough to have owned 10 different Tobias basses, over the years, including 3 Pre-Gibs, 2 U.S MTD 535-24s, 4 Gibson U.S Tobiases and 1 MTD Kingston. (I still own the 3 Pre-Gibs and 2 U.S Gibsons.) I'm also lucky to have had no terrible "Duds" amongst the bunch, but that doesn't mean they were all perfect and had no issues....
Out of the 4 Gibson-made Tobiases, I'd say 1 of them (a mahogany Killer B-5) was exceptional and had no issues, but the other 3 had something that needed work or fixing. The brand new lacewood Killer B-5 that I bought as my first ever Tobias bass, had a dodgy Bartolini pre-amp and would drain batteries in a number of days. I had to freight the pre-amp back to Gibson for a full replacement, which took months. (They did give me lots of free Tobias strings, to make up for it, though!) The '95 Classic 5 that I bought used, had curved pickups that didn't match the (nearly flat) radius of the fingerboard, so the B and G strings sounded weak and there was no adjustment that would fix it. I had to replace the pickups with flat Bartolini CB models, to get it to sound decent. The Growler 5 that I bought recently and still own, has about 4 really high frets up towards the nut and needs a fret-level, before I can get the action down to a normal level. (Even the double truss-rod can't flatten that part of the neck out, so I suspect it has been that way since being built. I could be wrong...)
As far as the Pre-Gibson Tobiases go, the build quality, ergonomics and sound has been exceptional, in all 3 cases. My oldest one, a Basic 6 fretless, is near mint condition and all-original. (And sounds glorious!) The Classic and Signature did have to have their pre-amps replaced, as they just started to distort and crackle, simply due to old age. But the necks are all close to perfect and very flat, plus very good to adjust, due to the double truss-rod setup. The sound is typically a lot warmer than the MTD basses, more like the sound of the Gibson Tobiases. (The really early "drop-shoulder" pickups are very fat and warm, like an early Ernie Ball Stingray sound.)
As far as the MTD USA basses go, I've had two (mint-condition) used MTD 535-24s and they have been amazing instruments - stunning to look at, top-notch build and attention to detail, light and comfortable. Very punchy and bright sound and incredibly responsive to different playing styles. (You can hear every single nuance of your playing, which is not always a good thing...LOL) However, one of them did have a serious neck issue that I couldn't get fixed, so I ended up selling it. Apparently, Mike Tobias has been known to say that the combination of an ash neck and ebony fingerboard is not a good one. Well, this first MTD that I bought had that combination and even though it was only a year old, had all sorts of weird high and low spots all over the neck and a considerable buzzing issue. Even after getting a full fret-level, it was still very inconsistent and I couldn't get the action down to where I wanted, so I moved it on. (I tried to convince Mike to give me a discount on a replacement neck, but because it was a used bass and had travelled "Down Under", he didn't want to come to the party.) But dayum, the thing sounded incredible, so I still wish I had kept it, despite that problem!!!
Anyway, hope that was interesting to some of you!
Cheers,
EG