I'm looking to make use of the Host Spot feature within pfsense and turn off my wireless router all together.
I'm not sure what you mean by Host Spot
- WiFi Access Point?
Does the TL-WN722N work with pfsense?
Probably not - it uses a different chipset from the Atheros USB WiFi chipset listed in the FreeBSD supported Hardware.
The WN722N appears to have a connector for an external antenna. Are you specifically looking for an adapter with a connector for an external antenna?
Can anyone recommend a USB card they are using with pfsense?
I'm using a Tenda W311U which uses the same chipset as that reported to be in the latest revision of the TL-WN321G. The WN321G has been reported to cause system problems when it is operated in Infrastructure mode (that is, associates with an Access Point).