I've figured out what the deal is with those inflated speed tests.
Someone linked to the ##DATA tuning of the HA, and I've used it long before I saw it mentioned here. However, I saw some people getting higher speeds with certain HA's and thought I'd give it a try.
While connecting to one certain HA (I didn't try EVERY one), it seems that the gateway/HA implemented some sort of compression. I tested while over 10mbit on a device not capable of even 5mbit. If image quality looks poor, it may be compressed to speed things up.