Personally, if you've already made the decision 
that you're going to sink money into a dream cel, 
I would go for your ULTIMATE dream cel.  As 
Starfighter said, the chance of that one coming 
around again is slim to none... and you might be 
kicking yourself later for letting the chance 
slip away.

But its ultimately your decision ^_^  Just as 
long as your happy with what you decide!

Good luck!  And congrats on finding at least 
finding your dream cels ^_~

-Kamiki