Digibit R1 works and has also support for 3rd. party firmware GitHub - perexg/satip-axe: A custom firmware with minisatip for Inverto IDL-400s/Grundig GSS.BOX/Telestar Digibit R1 has a known HW problem that if you OTA epg scan or idle scan at all >=3-4 tuner the same time the box crashes - if you limit this at 2 tuners (its just about scanning, epg, watching tv with every 4 tuners is no problem) everything works fine and you have the opportunity to use Sat>IP over TCP which improve the stream quality at problematic networks (this only works with the mod fw)
triax works, megasat works and nothing too obvious