Advantages of MIDI over USB?

[4damind]

Both can be crap.
The class compliant drivers are not the best solution because they have no multi-client support. People using different applications the same time (eventually a controller application or a simple Sysex helper tool etc) will have a problem.
Proprietary drivers for USB Midi having not much sense if the firmware/driver implementation is crap (like with mostly all M-Audio stuff).
The same when using a USB Midi interface.

IMO there is not the best way. But I would say that some external Midi interfaces are more focused to good timing and giving the best results.
I compared some M-Audio midi stuff (Midisport 2x2, Axiom Pro 61, Delta1010) with a Emagic AMT8 USB Midi interface... There is a big difference with a proper timing! So I will say, it's in some parts more the drivers/firmware or some eventually internal optimization (timestamping or stuff) which makes the difference.

[mkdr]

My Akai MPK has one weird "problem" when used over USB. When you play the first few notes after having plugged it in, the device "hangs" for about 5 seconds and stops sending MIDI. Then it rapid-fires the notes you played during this time. After this, it's completely stable.

This issue isn't unique to your MPK, it's a bug in how Windows (Win Vista and Win7) handles class compliant MIDI devices. Windows will pass thrrough the first few MIDI messages it receives (between 4 and 64 bytes), then it will drop a few messages (between 16 and 128 bytes) and then the device will work fine. It's really frustrating to test class compliant MIDI devices in Windows because of this issue. I have to turn my controllers on and off a lot so I have to remember to move the pitch bender a bunch as part of any test procedure.

Of course this isn't a problem with MIDI devices that have their own driver (Novation, M-Audio) but since Akai/Alesis/Numark rely on Windows' USB Audio class driver, their controllers suffer from the limitations and bugs in that driver.

That's odd.. I don't have any bugs on my driver-less midi devices.

There's no silly port number limit either..
I've got 18 midi ports.

And i used to have 12 or 14 when i was back in WinXP and in Win98.

But i do think that usb midi is sh*t.. When i originally switched from my 8 port serial rack device to usb, i was devastated how bad that was.. It's become much better now though.

I'm running midi from Delta1010's, E-MU XMidi 2x2's and few devices with straight usb-midi.