**On the first computer with the AC88, I have attached two 14dbi Flat Panel directional antennas, one extended mount w/stock antenna and one stock antenna in its original (4-port) mount. I have been able to get signals from -43 to -50 with my data transfer speeds at over 100Mbps and no drops I am able to connect at 450Mbps with two channels.
I use this card now at my router computer station to monitor channel signals with a pair of Alfa9s. The AC55BT is a fine card but was I not getting enough signal (-55 to -60) with several drops using external antennas, as the included stock antenna on the AC55BT is less than to be desired. I replaced the AC55BT 2x2 card with a AC88 on my second computer as I needed the extra power and antennas. I require a live HD video feed from my CNC machine and for transferring files. I have two side-by-side workstation computers that are two floors down and on the opposite side of the building from the router the signal needs to cross through my kitchen on the first floor with stone tiles and granite tops.
I am running a 2.4ghz/802.11n network signal. My setup includes the Linksys WRT1900ACv2 router with two external Alfa 9dBi OMNI-Directional antennas and a two-port dual Hawking Directional 9dBI (HD9DP) antennas. I currently own three Asus adapters, one PCE-AC55BT B1 2x2 and two Asus PCE-AC88 4x4.