Brent:

We recommend the Direct system in the case where your X5 may be teetering on the cutoff dates of compatibility with the newer system..

It's better to try the Direct, as you gain several features:

Full Sirius Text such as:

-Song Text
-Artist Text
-Album Text

In your case, however, the Direct system most likely isn't going to work. The Connect system will display channel numbers only. You can still navigate via the steering wheel and radio, you just won't have text.

Either way, as long as you have Sirius in some form, it doesn't really matter!