Dave Smith Instruments SYNTHESIZERS

OK I've been playing with my mono Evolver now for a while and while 
it is great stuff I would really now like to get at least 2 and maybe 
3 note polyphony with it. (Hey my music teacher taught me that you 
need 3 notes for a chord )

I could buy the rack unit and get up to 4 notes ....problem 
solved ..., but that's $1300+ ....or I can get 1 or 2 mono units used 
for half of that price and chain them. 

but here's the gist of my question, if I have a sound patch on the 
first mono synth that I like (and spent hours getting just right) 
would I then have to meticulously replicate that on each of the 
downstream evolvers? or does the first one control the other two with 
respect to oscillators and mod routing etc, etc. ....and if I have to 
replicate the patch, does the sysex send in the first deliver the 
patch to  the second and third units easily?

also in a chained environment , how do MIDI program changes work? 

If I have to config all three in parallel, that seems like a real 
time killer (maybe I should just pony up and get the rack) 

thanks to all in this group for your thoughts

Brian