Rabbit users - which core should I choose ?

["Kevin Hawkins" <lists@xxxxxxx>]

Would appreciate some guidance here. About to buy a Rabbit development
system but have a couple of questions for someone who already develops with
these. Mainly around recommendation of which unit to go for - I need
Ethernet btw
Once I buy the development system for one core module I assume I can
use it directly on all the other core modules (I never have to buy anything
different, pinouts the same etc ?) and that code I write can just be
recompiled for different cores ?
So why would people choose say the 2200 cores over the 3000 cores eg
the 2200 vs the 3010 - the latter is more powerful and has more I/O at the
same cost - currently I am veering towards a 3000 dev kit - is this a
sensible choice ? - it looks like the lowest cost unit in small quantities
to produce the best priced final product.
However the 2100 dev kit is the only one that includes the higher
capacity 512K/512K, all the rest bundle the smaller family members 256/128
device as standard. - The  bigger device may be better for initial
development (code bloat). Can I buy this dev kit and use it with the 3000
cores too ? Or just buy any dev kit and a couple of cores as needed.
Lastly , will I find that I should have (need) the extra =B5C/OS-II
Real-Time Kernel as well ? Application is the xAP gateway (embedded
version=
)
- ie Ethernet udp plus 2 serial ports at mid speed.

Kevin