I only used Vue 5 for a little while before Infinite was released.  I never had any problems, but with the eco systems being Vue 5 Infinite only, it's impossible for me to go back. 

They also have said the 6 word for sometime this year.  Hard to say if upgrade now or wait and see.  I think someone was selling their copy of Vue 5 Infinite on e-bay.  You might want to check out that path...

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