I don't think so. I would rather have a model A+. The "avoid SD card issues" statement is not really valid these days, given that earlier SD card issues seem to have been resolved and you can boot from different media quite easily.
The A+ costs about GBP20 or Euro 24 from a UK supplier (as an example).
With a CM3 it may be a better case, performance wise. That does not help the re-use of the CM (I have two of them).
It is another way of getting a different form factor and a non-SD card solution which is cheaper than the CM / CM3 dev kits. But no display or camera support either.
Just my view