No - that’s good, I wanted to check you had the CAT18 modem.
So long as the transit is using the same frequencies as the tablet, and you haven’t got every inline traffic management feature enabled on the transit (firewall, content blocking, DPI etc) which might slow thngs down, then I see no reason why the Transit shouldn’t perform as well as the tablet.
If you look about on the forum here you’ll find a couple of ‘my phone is faster than my router’ threads and these normally end up being a bad hardware comparison (because the phone has a much faster modem that the Peplink its being compared to), or a mobile network issue where the transit is told to use different frequencies or has different network prioritisation by the tower / mobile network than the phone.
Signal strength (RSSI) isn’t everything. Look at RSRP and RSRQ as your signal quality indicators. The throughput on the dashboard page is a snapshot in time measurement. The real time graphs on the status page are the accurate measure of throughput.
I think you likely need to gather some evidence (regular speedtests and use InCOntrol2 to monitor signla measurements whilst stationary for a few days) to be sure there is a speed issue. Once you are sure, log a ticket withe engineering with your findings.
There is also this thread that might be applicable to you if you are in the US? US Data Plan on LTE CAT-18 Models