Thanks!
There is no need to rush the decision, you can always upgrade from Opus Light to Pro for the difference in price (besides, there are usually discounts around various holidays) 
I've noticed you mentioned that your 30 day trial is coming to an end, did you know that you can extend your Opus Pro trial for another 60 days? So in essence Opus Pro trial can last as long as 90 days total.
AFAIK you can switch between Light and Pro versions in Help > Licence Manager while trial is active so you can compare differences in realtime.