The BC250D is a discontinued TrunkTracker III scanner that will track Motorola analog, Motorola 3600 baud P25 digital mixed-mode systems (with the optional BCi25 card), EDACS (wide, narrow, and SCAT), and regular LTR systems. http://wiki.radioreference.com/index.php/BC250D
The BC250D is a great radio, but will not survive the Motorola rebanding if you intend to use it for Motorola systems.
I will only use the conventionnal mode (i don't need racing system, and trunking). In this case , Is the Sc230 has more advantage with close call and dynamic memory?
If you are look for a good scanner that is not digital then yes the bc250d is great but if you are looking for something digital then you should look into the 296d that is the easy scanner to work with .That also goes up to the new 9600 digital so you will be set for a long time .