There is only one actual company (I believe) making HD-Base-T chip sets such as the one within the unit you linked to.
HD-Base-T has been widely adopted by major manufacturers as a 'standard'. This means that the audio and video portions on the front end and back end are interchangable from one brand to another. Crestron, AMX, Panasonic, Extron, Aurora Multimedia, PureLink, and others have all started to use HD-Base-T as their choice of product for long haul HDMI extension.
The use of Cat-5/6 allows the transmission of the HDMI signal beyhond 300 feet without issue in most cases and provides an 'exact length' extension which is bascially impossible in the world of HDMI by itself.
Now, the previous extender... Read the reviews of it... Poorly made, sometimes works, sometimes doesn't. A lot of very poor marks on that product (about 25% are 1 star reviews), and I'm not sure if anyone has really pushed it hard with 1080p with HD audio. That is where HD-Base-T tends to excel in that it supports 1080p without issue, and has channels to further support Ethernet (10/100) as well as data communications such as IR or RS-232 along the same single Cat-X cable.
Personally, I've tried almost every single HDMI extender Monoprice has sold and none have come close to matching up with their newest HD-Base-T extenders. Many worked fine for limited distance video up to 1080i, but as soon as the PS3 was connected to my 3D plasma, they failed to deliver. The second I plugged in the HD-Base-T units, it recognized the signal, recognized the TV, and delievered full HD 1080p without a hiccup.
I recently had a chance to play with the new Panasonic laser/LED hybrid projector, which will be installed shortly, and it has a HD-Base-T receiver integrated into the projector. It can either be set to Ethernet only mode, or can be set to HD-Base-T mode. In HD-Base-T mode it accepts control, Ethernet, audio, and video up to 1080p over a single cat-x cable. The theory is that any HD-Base-T compliant transmitter should work with this projector.
I put it to the test with transmitters from Crestron, AMX, Extron, Aurora Multimedia, and both Monoprice models. Every single one of them, without exception, delivered as promised. 1080p audio and video over a single piece of cat-5e cabling. To get serious, I took three 100' lengths of cat-5e and used a standard coupler to put them together and one final 12' piece coupled to the end. 312' of cat-5e with 3 couplers between them all... No issues.
There are very few products that get the industry motivated in such a manner, but HD-Base-T has moved towards being accepted as a 'industry-standard' within the last couple of years. It does carry a higher price tag right now, but may eventually show up on consumer televisions and sources within the next few years.