I have personally owned a D3, Z2 and Z3(60gig upgrade), a Kenwood DNX8120, and now the F900bt and I can honestly say that I miss my Z3 (sold on ebay for 1000) It was slow, but it was refreshing to have everything working to maximum capacity. The D3 has a great deal of perks, especially the blutooth clarity. The Kenwood was the fastest interface I've experienced but I didnt like the fact that I didnt have the 3D mapping features. Out of them all, I really miss my Z3. I pray that the firmware update allows pioneer to deliver on the high volume of promises of the f series.