It depends on how you want your music. I prefer accessing my music exactly how you access them on my iPod. For example: I'd like to go through artists, songs, albums, genres, etc,etc.

On the other hand, if you're OK and contented with just streaming the iPod audio directly to your X5 sound system, then the GROM would suffice. Very clean sound coming from the iPod! Bonus points for GROM because you can even directly access your first 5 iPod playlists through the MID controls and steering wheel buttons. I'm sure you'd be happy with it.

My comment and rating for the GROM reflects MY preferences on how I want to access my music. Thus, I have combined an Alpine EX-10 (to access the iPod contents like an iPod) and kept the GROM (audio from the Alpine EX-10 3.5mm output - plugged to the 3.5mm Auxiliary input of the GROM). This process avoids the noisy FM transmitter!

I'm currently looking at the DICE but not sure yet if I'm willing to give up the 'iPod like' interface I'm currently enjoying right now. I hope this helps. Thanks.