I'm not fond of the large screen, but can live with it. I'm not really interested in album art, etc. I just want to listen to the music.
Well it isn't just for album art, that is only one aspect of it. You can review bio info on the artist, review a list of previous songs played, then you have the Library and can review a list of songs available, along with playlist. There are many reason for having a nice screen. But with all that said, I personally do like Album art and I honestly think that is an attractive aspect of the device.
Is clear protective shield available from invisible shield ? I think that is the name of the company. Clearly the arm band is not protective of the screen in any way.
Invisible shield would be glad to make one for the device, but some brave soul has to send their device to them so that they can use it to create one. I personally just purchased an invisible shield for another device and used it to protect my G2 display. It took a little effort given that the invisible shield had to be custom cut by me to fit properly.
In terms of the arm band, I have no interest in one, so I wouldn't know if it protects the device or not.
How long does it take the device to boot up after turning it on ?
If the device is totally off, then it takes about 45 seconds. If the device is just sleep mode then it come on almost immediately. One interesting tid bit the device stays in sleep mode about 2 hours and if left in sleep mode longer than that it will do an auto shut down to conserve battery life. So in those case the restart time of course is much longer. I wish the start up time was a bit shorter, but it's something you get use too.
How do current owners like the media buttons ? Do they feel solid, cheap, etc ?
Honestly I am not a real big fan of wheels that also act as a selection button. But I found this setup to work okay. I have accidentally scrolled a bit while trying to push the button and therefor went into the wrong menu item, but it is something you just have to pay a bit of attention too.
In regards to the Favorite and Ban Buttons at the top of the display. I find them much too sensitive and I have often times favored and or banned songs I didn't intend too. But now that I am aware of this, I have started using the lock key on the side. This has helped, but I still feel these buttons are overly sensitive and really should have had better placement if they were going to make them so sensitive.
Is the current firmware on the device allowing navigation to be smooth ?
Firmware updates are downloaded when available at the end of a refresh and will install when you reboot the device. In regards to the menus and navigation of the device I find it works very smoothly. I have zero complaints on this.
Skipped the rest of your questions because I am not an armband user and have no idea bout it.
The one thing that I really think they need to add is sleep mode, so that you can set the device to play for a period of time the user selects and then go into sleep mode. I usually like to listen for 60 to 90 minutes before bed at night.