Others say...

"Inexpensive Midi Interface"
I ordered this item with fingers crossed that I could get into computer-based music recording without spending a fortune. I have an older Korg SP-100 keyboard and used this cable to connect it to my computer which runs Tracktion 3 recording software. Having installed the software and some VST plugins for instrument sounds, and having connected my keyboard via this usb/midi cable and done a few rounds of simple recording to test the setup, I am happy to report that everything seems to be working well. I can't really comment on the quality or longevity of the cable since I've only had it a short while, but at less than $10 my expectations won't be hard to exceed. If you need a simple & cheap way to use a midi controller with your computer, this seems like a great way to go. And for the record, my computer runs Vista Home Premium and there have been no compatibility or driver issues.

"May not work with your equipment"
I hate leaving reviews claiming something's "broken", but in this case there were some serious problems. So my problems:

1. The device does not handle run-on MIDI commands properly. I doubt that many modern MIDI devices use run-on commands, as they were a somewhat confusing bit-saving mechanism from the 20th century. The keyboard I used was a Kurzweil SP-88. I suspect this is a design-defect in the product. More on this below.

2. The device would not enumerate on my main PC. That box is a custom-built machine using a P5B Deluxe motherboard which has never had any problems with any other USB devices. I even tried clocking the box down to normal speeds; Vista gives me a vague error about the device malfunctioning, and Ubuntu gives me a read error during enumeration in dmesg (which, to be fair, wasn't any more useful in this context.)

3. For all the reviewers who said the cable was labeled backwards: MIDI cables are always connected so that the "OUT" of one device goes to the "IN" of another device. MIDI supports a ring-shaped daisy-chain of devices that way. This cable was not labeled backwards.

Elaborating on point 1:

On the wrong equipment, when you do this:
1. Press-and-hold key1.
2. Press-and-hold key2.
3. Release key1.
4. Release key2.

You get this:
1. Press-and-hold key1.
2. Press-and-hold key2.
3. Release key1.
4. Press-and-hold key2 again.

For those technically inclined, here's the data stream from my SP-88 using the old serial cable I was replacing (I had to resurrect a dead machine to get this; I'm forging note velocities for easier comparison):
90 40 45 3c 48 80 40 62 3c 61

Here's what this product read:
90 40 45 90 3c 48 80 40 62 90 3c 61

Here's the nearest valid sequence it could have provided:
90 40 45 90 3c 48 80 40 62 80 3c 61

Note the 80 instead of 90 in the third-to-last byte - "80" means "note off", "90" means "note on". This was a deal-killer for me; your mileage may vary.

I replaced the cable with an M-Audio cable from a local shop for 3x the price; that cable also reprocesses run-on commands, but does it appropriately (the third sequence above is what I would get.)

The seller was courteous and provided a full refund, including shipping, so all I lost to them was time. I'd buy from these guys again, just not this product.

"Inexpensive and easy to use"
This is definately a handy little product and well worth the few bucks compared to other midi to usb converters.

"Works fine"
The cable works fine, no fuss. The IN/OUT markings mentioned by the last reviewer do seem to be backwards, but it was the same with the last MIDI cable I had so maybe this is just the way it is with MIDI?

"MIDI/USB cable"
The cable functions properly but the Midi end is marked wrong. The In is the Out and the Out is the In. Hopefully this will save somebody else a few hours of messing around getting it to work with Vista.