OK, it cannot even beat my 3 years old Huawei MiFi E5776 which is only an LTE MiFi.
Yes, the internal antenna of 790s is obviously not that good, after plugging in external antenna, it only increases 5Mbps to 10Mbps.

I applied online mnp to Digi and I received my SIM card within 48 hrs but to approve my mnp from my ex telco to Digi is another story. First approval text came in after 72 hrs and late in the day to confirm my request to mnp. After my reply it took almost another 24 hrs. before I was allowed to port, it was late in the evening 5 working days (120hrs later) from the time I submitted my online application. I was told I was lucky as it can take at least 7 working days. You really have to be patient with the whole process.

No need. Call CS and will activate for you or via LiveChat.

Going through Digi Centre only if your plan has no RLH included, this is not the case for Infinite 150 because it is bundled with RLH.