Agreed. I'm using a DEH-860MP myself and the tuning capabilites on it are great. Fantastic SQ as well.The deck also features Digital Time Correction as well for finnding that sweet spot.

 

My alpine has all the crossovers built in for running 2 way or 3 way.
I use it in 2 way mode, so i have hpf on for front and rear.
If you don't use rear speakers, you can use the biult in crossovers for front mid & tweet.