Its also very hard to find information on such a comparison. In general I think both cards are based on Qualcomm chips (see here). On the FCC website you can find out which chip the Broadmobi card uses but unfortunately not for the Gemalto card. But even with knowing the exact modem IC its hard to find information since Qualcomm is not really open with that.
The Gemalto card offers LTE cat 3. The Broadmobi offers Cat4 (a later revision). Hence I would assume the modem IC Broadmobi uses is a slightly newer modem and maybe has a better reception (due to more development time on the later IC version). But thats a big assumption…
Maybe you find some additional information on the FCC website. At least the uplink (from the phone to the base station) part can be compared using the output power listed on the FCC site of boths cards PLS8-US BM818. I did not see any information on the sensitivity for the downlink.