Select the Wireless tab; from the wireless basic settings go to 'Max TX rate' and select MCS7 or MCS12 (should be MCS15 by default). Save, wait for the link to re-propagate and redo the tests. Seeing...

sounds good, try switching to 20Mhz / MCS12 and report back

As a rule of thumb, a very very rough estimate given optimal circumstances you should expect real bandwidth according to the values below. I cannot stress enough how channel selection / width as well...

3 CPEs that I bought in Europe as of late, they all came from Germany and there was no such limit imposed...all v1.1 :/

Also in the process of 'venturing' on a similar wireless project, currently in the final stages of receiving some missing parts, so I'd expect this to materialise over the course of the next two...

I do re-affirm that with current versions of both browsers (Safari / Chrome), the procedure as I described above works just fine, i.e. one can have both windows up concurrently running on one browser...