I was at QC Charge in Carlsbad this weekend, they are certainly one of those places that fixes a $20,000 battery for $4,000. Had one apart on the floor when I was there. Just needed to touch up the solder on the bad module, another one had a bad BMS that showed as a couple of bad modules. BTW, QC pointed out that Tesla doesn't sell ANY "new" battery packs, just remanufactured. If they run out of them they might make you a new one, but they don't want the next guy to demand a new one too, so they sell them all as 'reman'.
I don't know about going with a replacement module repair though. I was talking to the repair guy and he said that they have to match the module they replace in your pack to the same capabilities of the remaining modules or it will cause more problems, so I come in with 242K miles on my pack and your gonna find a module that will mate with that and I shouldn't expect another problem down the road at 252K miles? Seems like unless I have a pretty young car that's just outta warranty I'd be better off with the reman pack for $20,000 or less as prices keep coming down, and I may get another 100K outta that pack.
QC wants to branch out to towns that have more EVs, I suggested Alameda, but Palo Alto probably has more, and more disposable income.