Well, not really. I include fax capabilities in my "v.everything" tagline, and both of these modems have it, and both come with appropriate fax software. That's the good news. The bad news is that my success rate with receiving and sending faxes has been low, although there are several reasons for that.
The Supra comes with FaxSTF from STF Technologies, and I have few complaints about FaxSTF. STF designed a decent interface, the software handles most things automatically (like bringing up a non-modal status window automatically when a fax comes in), and offers features you might normally want from a fax machine. My few complaints are that STF isn't great about sharing the serial port with other communications programs and that it includes a lot of pieces, including two DAs, an application, a Control Panel, an extension, and Chooser device. That's a lot to keep straight, and the fact that you have to configure most everything from within the Chooser device bothers me. I'd like STF to bring the number of pieces down to an extension that sends and receives and has a Control Panel interface for configuring the software, a single DA for feedback and sending quick text faxes, and the otherwise nice application for managing phone books and viewing faxes.
FaxSTF insists on taking over the modem if you turn on auto-answer, and not all communications programs deal well with making FaxSTF relinquish control of the serial port. My automatic mail sessions in America Online, uAccess, and Navigator all work, but often I come in to see that the modem is no longer auto-answering and that uAccess is complaining about not being able to access the serial port. Still, I could suffer with FaxSTF the way it stands, and in conjunction with the Supra modem it worked about half of the time. Perhaps one of the ROM upgrades will help.
QuickLink II Fax from Smith Micro originally had real problems. I can overlook the functional troubles for the moment, since I was working with a beta version and most of the functional problems seem to have disappeared, although when QuickLink II has Fax Receiving on, at least uAccess cannot access the serial port. (PPI owners on CompuServe can get the latest software by asking in the Practical Peripherals forum, GO PPIFORUM, or you can call PPI and order it, with disk and manual, for $34.95.) More serious in my opinion are the problems with the interface. QLIIFax has two basic interface problems. First, the fax software comes in the same program as a normal telecommunications program, so you can use it for calling BBSs as well as sending faxes. This may sound good, but the telecom part of the program is unimpressive, if functional, and doesn't support ZMODEM. Including menus with data and fax commands clutters and confuses the interface significantly. Second, although Smith Micro significantly revamped the interface when I and other complained about it, I'm still not impressed. It's prettier and there are fewer modal dialogs, but it still doesn't look or work as smoothly as FaxSTF.
In both apps, the procedure for creating a fax is simple - merely choose the fax driver in the Chooser and print the document. You can either send the document immediately or schedule sending for a later date. Of course, no matter what you do (even with using TrueType or ATM fonts, a necessity for faxing), the document will look ugly on the other end and in most cases will print on non-recyclable paper. Frankly, although I admit their utility, I think faxes generally waste paper. Although I don't know if they have released it yet, STF is working on a program that does optical character recognition on incoming faxes, turning them from disk-hungry bitmaps into usable, editable text files. More power to them, and if possible, we'll review it here.
I suspect that when all is said and done, both modems will eventually work equally well at sending and receiving faxes, although people I've spoken with say that fax modems are never as reliable as regular fax machines, which is a shame. I have had trouble primarily with receiving faxes, which currently arrive successfully about 10% of the time. At the moment, I have to give the nod to the Supra modem and its FaxSTF software, or to a the PPI modem with the additional purchase of FaxSTF (which you can buy separately, and it's included in MicroPhone Pro from Software Ventures), for those who anticipate using the fax features often. Others have also recommended the Global Village modems and their proprietary software, but I've never even seen it.