OLP Stingray 5: G-string tends to pop out of the nut randomly, especially when playing slap. Scratchy pots. Strap button comes loose.
I love OLPs, but they're not without flaws, true.
G string popping out the nut: I have 2 OLP MM2. An earlier one and a newer one. The necks are different. On teh newer one, teh strings pass over the nut with a sharper angle. The older one... the strings were almost parallel. You had to wind up a lot of string to make it a bit lower. This meant the strings (especially the D, in my case) could rattle on the nut.
Solution: I bought a bar string retainer to push teh strings down above the nut, so that they come up at a sharper angle. Cheap and easy, and it works.
Scratchy pots... yeah, I changed mine. But you can extend ther life using some contact cleaner, again cheap.
Strap button loose... basswood is very soft. I had to jam by strap holes with extra wood (matchsticks) to make sure the screws are firm. Again easy to do...
Flaws in my basses:
Warwick Corvette $$: not exactly a flaw, but the neck is chunkier than I'd like, however it sounds great. A couple of polepieces appeared to lack grounding and can hum when touched, but it never happens during playing so i'm not doing anything about it.
OLP MM2, newer: crap pots, bad fret levelling, uninspiring pickup. I have dealt with all that and installed a Seymour Duncan SMB-4A pickup and an STC-3M3 preamp. beautiful. I play this bass all teh time. The bridge is slightly misaligned... should be about 2mm to teh left. One day i'll fix that.
OLP MM2, older: strings have little angle at the nut: rattling. Now fixed. Uninspiring pickup: fixed. Heavy body (on this one).
Tanglewood Warrior: horn too short, very bad balance. Great sound and everything but severe neck dive due to position of the strap button. Couldn't find an alternative location that worked well. Shame. Sold it because of that. The pickup (big MM humbucker) had non-grounded polepieces that hummed when touched. It required a creative mind to be able to fix that.
Vintage EJM96 Jazz bass: fantastic player, but electronics very very noisy. Noisy pickups. Fixed electronics through shielding, pickups were microphonic... sold the bass before I replaced pickups
Tanglewood Warrior III. Great bass. But neck a bit on the chunky side. Frets needed work, G string choking on some frets. Bridge 3mm out (I corrected that). Pretty fretboard overhang meant reduced space for popping strings. I sold that one too before I fixed everything.