There are few differences between infinite and complete. You can see the full list in the links in the posts above.
In my opinion they dont justify the additional cost.
If money is no object - by all means, buy infinite. Otherwise, it depends what features you think you will need.
Important note: The real problem is that there is no official  way to move from complete to infinite if you change your mind or your needs change in the future.
There is a free trial version of both versions of the program. I think the version of infinite is not time limited, so you can use it as long as you want, and figure out if you need the extra features. If you havnt used vue at all - that is probably the wisest way to decide.

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Man Ray, modernist painter
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