Welcome to FT op. If you want to ensure that you get 2 seats and that they are together, now is the time. Isle seats tend to go as time goes on. If you wait, and only window seats are left when you purchase, you may find it difficult to get the person next to you, or your wife, to give up the isle seat in an effort to trade with one of you.

if you are prepared to pay the current price, do it now and relax.