I have a 4 string OLP. I think it's around about a 2001 model with a chinese elm 3 piece body, (natural finish no figured top) and maple fretboard. I got it second hand for next to nothing.
I would describe the neck profile as very fat; baseball bat type. The fingerboard feels and looks less curved than the 9.5" on my jazz bass, but more curved than my carvin LB75. The OLP was a bit tiring until I got used it to it. I couldn't tell you what the radius is for sure.
Honestly, passive I didn't like the sound at all, not enough bass and very weedy. II put in a seymour smb4a and that improved things a hell of a lot, i.e. more bass and treble, but then I like aggressive tones. However when i put in a seymour stc3m3 premamp (routing required) the thing turned into an absolute beast. The natural bass thump is really accentuated and its slap tone is amazing. If you want air movement here you go..........
I think you'll need to spend some money to get the best out of it but it's my first choice bass for slap (and I have some expensive basses) and if I want deep bass or reggae tones it's the only choice.
I am aware that I have spent more on this bass than it's worth, but i spent slowly. I have also put on hipshot tuners and a d tuner and I wouldn't have done that if i didn't think it worth it. (25 years on bass and counting). I now have no desire to buy a musicman as I think this is 105% (or more) of a stingray as is.
Get a good one though, I think the quality control comment is justified.