In my current Lexus ive had the following systems installed:
Kenwood DNX-7029 + KNA-G520
Kenwood DNX8022BT
Pioneer AVICF900BT
Kenwood DNX9240BT
And...i must say...i couldnt wait to get rid of the Pioneer unit...sold it off after just two months (i usually keep my un units 10-12 months!)...and got the DNX9240BT...and i cant begin to tell you have good the Kenwood's are compared to the Pioneers

For the record ive also tested all available 2-DIN MM systems the last 4-5 years from Kenwood, Pioneer, Alpine, Clarion, Sony + a few other non-mentionables... And i must say, nothing even comes close to the DNX9240BT. However...coming from the DNX8220 (i leave out the two months of AVICF900BT ownership here)...afirst i was abit disapointed about the DNX9240 because of the now fixed recource-hog bug. Updated firmware...and voila. The worlds most complete 2-DIN navi system...for now atleast

And as for tips etc...heres my findings with the unit so far:
It will accept Topo-maps!

(Use Garmins mapsource software)
It offcourse uses the same poi speedtrap-files as Garmin.
You can buy the Garmin Maps, they are much cheaper than the Kenwood ones

(ive allready upgraded to "2010 first quarter" on my unit)
The "custom start up" screen has allready been mentioned, so i think i will shut up for now
