Typically for between $30-60. I've seen them sell recently for wild ranges. There are cheaper ones on ebay, but many without the boot disc. A GameBoy Player without the boot disc is little more than a paper weight, and finding boot discs by themselves is a near impossible task.
I honestly don't think its a problem, but if you're the kind of person to complain about the excellent NES-101 'dogbone' controller, then I suppose an OEM controller will not satisfy you. You may want to consider alternative Japanese controllers that would solve the problem.
The first is the Super GameBoy Commander, a controller designed with the SNES B and A buttons in mind as the primary buttons. This creates a problem of playing some games that require the shoulder triggers as they are moved to the face, but I think it's a great solution.
The other alternative I can think of is the Hori Fighting Commander, which uses a six button Genesis style layout. Again, the triggers are moved to the face, making some GBA games too awkward to play using this, but it sounds perfect for games like Mario vs Donkey Kong, which you complained about.
I like the GameBoy Player. It's the primary reason I keep a GameCube around, since my modded Wii can play all GameCube games from any region. But there's a couple reasons why the GameBoy Player does
not make the Super Retro Advance pointless.
First of all, the video output of the GameBoy Player is quite blurry, using a softening filter that is present even though component video.Using the same games and the same tv, I can tell you the video output of the Super Retro Advance is cleaner, clearer, and the colors more vivid. When I get a chance, I will take side by side comparison screenshots if you'd like.
Moving on to audio, this is another case where the Super Retro Advance outclasses the GameBoy Player. When compared, the GameBoy Player audio output is much more muffled and softer sounding to the audio output form an actual GameBoy Advance or the Super Retro Advance.
Although I'm not an audio expert by any means, I was told by ace9921:
On the GameBoy Advance's CPU, there are two analog audio outputs, one for the left channel, the other for the right.
But on the GameCube's Parallel port where the GameBoy Player plugs into, there are no analog audio inputs!
So what's done instead is to pass the audio through an ADC to make it digital, then it gets converted to analog again with the DAC inside the GameCube along with its RIDICULOUS low-pass filtering.
Analog to digital, and then back to analog.
Leaving the larger screen filling video output of the SRA vs the windowed GameBoy Player up to presonal preference and not something I'm going to argue for or against, the other big negative the GameBoy Player has is the controller.
Even with the Hori Digital Controller, the GameCube controller is NOT well suited for GameBoy Advance games, with its massive A and undersized B buttons. The SNES controller is a much more natural fit.
The one advantage the GB Player has is the ability to play GB and GBC games which the SRA does not, which is unfortunate. However, examining the motherboard, it says the revsion is only 1.0. It is possible GB/GBC support may be added in later.
Anyhow, I'll be testing games and give a report of a list of games I've tried and the outcomes of each.