With LTE speeds, I take it you mean modem data transfer speeds? Thales PLS8 has dl max 100 and up 50 Mbps, Broadmobi BM818 is 150/50Mbps. Comparisons of features and links here.
As for AT commands for modems, while searching for the modem info, I came across this showing some commands. As for using them, I haven’t had the chance to as a certain package has not been sent yet.