If the 70 is less expensive, get it. You will not notice any difference between the two other than the 70 has a hot shoe.
It seems the biggest difference is that the 70 does not have a built-in flash/light, where the 90 does.
Right now, they are approximately the same price, but the 70 has the added expense of the external light.
Is it better to go with built-in light?
Are the external lights fragile and thus likely to need replacement often?
Are there any other performance differences between them?
Also, the 90 is listed as "NEW" on canon's website. Would that make it more advantageous to buy over the 70?
Thanks. (I need to buy this weekend: trips and graduation and tons of other events coming up)

Chowhound
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