Wait atleast 60 working days before you make an info pass appt.
As for the info pass: You question was if anyone recommends going with wifey or alone.
It would be great if you guys can go together. However, its not required.
To be on the safe side, I would have a good reason why I came alone - incase they decide to ask. There is always that 1% chance that they might ask.
If your spouse cannot go because of work... say that.