Personally, I tested many boxes on IPTV including Nvidia Shield, and I found that all hisilicon based chips are by far the best boxes in IPTV, I am not sure about recording, to be honest, but it is operating IPTV very smoothly.
I believe OCTAGON SX888 V2 4K UHD IP E2 Linux Smart TV Receiver would be the best option because it is having dual os E2 Linux & Define OS Linux, and my test was in Define OS which I believe is one of the best OS for satellite receivers for regular use.
As per my understanding, it is a hardware limitation (Tuner) and it will be there regardless of which brand you are going to use, you can stream all channels but on the same TP, so more tuners means more channels with different TPs.
You can find good Android STB (Android AOSP not Android TV OS), but dual boot with Enigma2 I believe only hisilicon chip based are available but 90% of the options aren't having good Android OS, very basic Android OS.
There is one model having Android TV OS MECOOL KT1, but it has very bad reviews in the live channels app and no one manage to install oscam yet.
For Android AOSP there are some good options like GTMedia Combo 4K , the built quality is good and oscam is installed out of box and works well.
Both above android options are based on AMLogic Chipset, although Hisilicon is better, but Huawei company (HiSilicon Manufacture) is having many processor models that reaches end of life very fast due to the US embargo so the future for hisilicon is unknown, so better go for AMLogic based chips.
All android dvb-s2 4k options that are using AMLogic typically the same hardware, your choice should be based on software support only, and I personally recommend GTMedia Combo 4K.
Good Luck.
