Does anyone using NTT’s “Collabo Hikari” (MAP-E) in Japan have issues with VPNs?

I’m using NTT’s Collabo Hikari, which uses MAP-E (IPv4 over IPv6) . Most IPv4-only VPNs cause connection issues (disconnections). I beleive it is because they don’t handle IPv6 properly.

Current Setup & Workarounds (I use method 1 for my PC and 2 for my iPhone):

  1. Dual-Router Workaround:
    • Main router: IPoE (MAP-E)
    • Secondary router: PPPoE (IPv4-only)
    • When needed: Manually switch the default gateway to the PPPoE router and disable IPv6 on the device.
  2. IPv6-Compatible VPN:
    • Now using AirVPN (which supports IPv6) even in IPoE mode, avoiding the need to switch gateways manually.

Questions:

  1. Is the dual-router workaround common/smart for MAP-E in Japan? Any downsides or better approaches?
  2. What if I move to a MAP-E-only area? Are there better long-term solutions?
  3. IPv6-Compatible VPNs: Besides AirVPN, which VPNs work well with MAP-E? (Mullvad, IVPN, ProtonVPN?)

by ananasie