The program installs easily, though users may need to make adjustments to their firewall or router to get full use out of it. The website offers guidelines on how to do this for many of the most common configurations, but as with any such adjustments, the user is strongly cautioned to be sure they know what they are doing, lest they expose their system to invaders.
Use of the program is simple and intuitive, though the interface has that chunkily charming 'Visual BASIC' look to it. You may open search tabs (up to 10 in the free version) to look for sound files, video, software, or more. It is possible to filter searches on several criteria; for example, if you are looking for an audio file you know is several megabytes in size, you can filter out smaller files which are most likely trojans or viruses.
Searching brings up the major flaw with this software--the network. It uses two, Gnutella and its own proprietary Zepp network. Because it is a small program with few users, there are fewer files to be found. For example, a search for "Linux" under software revealed only 50 hits after 15 minutes of searching. By contrast, Shareaza showed over 400 hits in about three minutes. However, when actually downloading, I found Zultrax to be quite fast, faster than the competition for files of similar size. This is a notable benefit.
The Zepp network has some useful features. It uses falsification to distort the apparent data being sent, making it slightly harder to spy on users. It uses measures to try to detect programs spying on the network and lock them out. These features might make it preferable for users in nations where government monitoring of file transfers is likely.
The freeware version of the program has only minor limitations--a maximum of 200 search results and secondary priority in terms of network traffic as compared to the Pro version. Users who find Zultrax to be their P2P program of choice would benefit from the upgrade; casual users will probably be quite happy with the fully functional freeware version.