In your case you most likely will have zero advantage with a PRI vs SIP.
That’s because TWC’s PRI is SIP backbone, which means that with PRI they are giving you nothing but a SIP trunk to a PRI gateway at your site. That’s their demarc.
So on their end the technology is identical, they are just giving you a PRI handoff instead of Ethernet.
Spectrum PRI would then only make sense for legacy, non SIP capable PBXs or if you prefer PRI pricing model over SIP, cause they can differ very much.
Haven’t talked to TWC since they became Spectrum, but last I did this was the case, at least in my area.
Ask them if their PRI is SIP backbone or not. If that’s the case, no advantage for you with one or the other technology when it comes to reliability.
Of course there are still other providers out there still sell true traditional PRI, but that’s becoming rare.
So if your problems lie with the provider, you should have the same problems even if you had SIP trunks with them.