Sharing iTunes files between PC & Mac?

I use iTunes on both a PC (in my home office), and Mac (in my listening room, with Mac laptop connected to my DAC). Currently I have my music collection ripped to Apple Lossless and saved on an external hard drive connected by USB to my PC. I have created lots of playlists using my PC version of iTunes.

Currently, when I want to hear these files in my listening room, I open iTunes in my PC, then open iTunes on my Mac laptop in my listening room and connect wirelessly to my PC's itunes library through the iTunes "Shared" mode.

This seems to work fine but I have 3 questions:

1) Am I getting the same quality when listening to my mac/stereo when accessing my PC's shared iTunes library as I would get if I had those same music files wired directly to my Mac on an external hard drive? And would that be the same quality as accessing the hard drive from both PC and Mac on a wireless network?

2) Can I unplug a hard drive of Apple Lossless files from a PC and plug them into a Mac to use with Mac iTunes, and go back and forth without any problems?

3) Can I share iTunes metadata, such as playlists, ratings, etc., by creating them on iTunes for PC, saving them to an external hard drive, and accessing those files from the hard drive to my Mac? In other words will Mac iTunes read the iTunes Music Library (metadata) folder created using a PC?

I dont know if this will help but Appletv will stream music,pictures,movies etc. from any library of Itunes(PC or mac) including playlists,etc. - it will need to be hooked up to a monitor though. I stream from three diiferent locations to my home theater room and the remote codes work with my universal also - thanks,thymanst
I answered my own questions by attaching my second backup drive to my Mac laptop (which is hard-wired to my DAC).

The Mac connected directly to the hard drive read the Apple Lossless files created by the PC. The sound quality was SIGNIFICANTLY better than when the Mac accessed the files wirelessly from the PC iTunes 'shared' mode. FINALLY, I heard Audiophile quality sound from my computer music files!

I'm not sure if I would get the same great quality if the hard drive was on a wireless network, but for now, I am happy to just have the external hard drive plugged into my Mac laptop.

What I also found, was that the Mac could not access the iTunes Music Library (names of albums, songs, playlists, etc.). I had to have my Mac iTunes create that all over again, and with 300 gb of Apple Lossless files, this took my Mac about 6 hours to create. Now that it's created I'm good to go, though I do have to create all my playlists again from scratch.

But I am so excited to finally have great sound from these files.

Maybe you could help me make a choice??

I've been the fence to long and need to make a descion.
Have you hade any problems using your Mac laptop as your music server? I've read several diffrent review. Some say it will over heat, others pushing me towards a Mac Mini but I would still need a monitar, keyboard, ect. to run it.

Long story short..Are you happy using the Mac book and if you where starting over is that they way you would go now??

I use a MacBook Pro as my music server and it is fabulous. No problems at all. Highly recommended.
I am using a iBook G4(used) as my music server and have had no problems what so ever. I was going to upgrade my Jolida JD-100 cd player and set a budget of $3000. I decided to try a listen to the laptop server/dac combo to see what it was all about. I was amazed at the sound quality I got, it is MUCH improved over the Jolida which is no slouch, and I am currently using a very inexpensive dac I have $900 invested in the whole server set up. I will in the near future upgrade the dac to either a wavelength brick or a mhdt paradisea+ which will still put me way under my original $3000 budget. I think this is the first time in this hobby I have come in under budget and been very satisfied for an UPGRADE.

The only problems I have with using my mac laptop (4 year old iBook G4) is that it heats up quite a bit after a while. Maybe the newer models run cooler. I also have only 512k ram, which makes things a little slow when I'm running multiple apps while I'm sitting in the listening chair. I think if I were starting from scratch I would get a mac mini (w/ a small monitor that could be added when I rip music), and an iPhone or or an iPod Touch to use as a wireless remote (and also makes a nice portable player). I think the least expensive mac mini + an iPod touch would be less than a macbook.

Good luck, and let us know what you get and how it works. I'm certainly very pleased with my new setup.
In the original post you mention using iTunes on a PC and a MAC. You described the improvement directly attaching storage to the Mac vs wireless, but can you compare the sound quality of the PC vs the Mac?

Everything I've read hear says that iTunes on a PC results in very poor quality. Is the PC connected to a serious system like the Mac, or is it just backdround music?

I'm asking because I'm tryin to set up my older PC as a server and I've been avoiding iTunes in favor of JRiver software because of the reported problems with PC/iTunes.

Need to set the output in playback under setting in itunes on pc, and set to windows audio session.

on mac need to set ouput quality under midi controls. Ie set to 24/192 or 16/44.1 etc. 

most of the differences in quality I have found with people’s settings are because of those settings. People don’t know what they are doing and therefore think buying new boxes which do the thinkimg for them make the stereo aound better.

you also need to check the hardware settings of sound output to dac if on pc in sound in system settings. 
Macs are intel based, basically pc’s now. Also most 3.5mm headphone jacks on mavs 2/3 years old are also mini toslink optical outs.