The CS3.7 XO pic I’ve seen shows good coils but sandcast resistors and CYC MKT caps. The drivers are probably the best ever from Jim Thiel (ie, some of the best ever from any manufacturer) but the passive parts quality is wanting, IMO. If I had 3.7s I would certainly replace the resistors with Mills MRAs which are cost effective, high reward/low risk. Replacing the caps *might* be more risky but I would probably do that, too. There is a LOT of capacitance on that board, so might have to go outboard if replacing everything including the big electrolytics. I would start with the tweeter and midrange caps.
That said, waiting for Tom Thiel’s solution is probably advisable for the less adventuresome.