Booked flights to Rio for 3 months from now, just started thinking about visa. Planning to use iVisa since I’ve heard the official portal can be a bit clunky. Any reviews on whether I should use iVisa or not?
Three months out is a comfortable amount of time, but I’d still recommend applying sooner rather than later. Brazil e-visa processing typically takes up to 2 weeks, though it can sometimes be faster. Applying 4 to 6 weeks before your trip gives you a safe buffer in case there are any delays or you need to resubmit documents.
On iVisa, I’ve used them for a visa application before and found it a smooth experience. The form is clear, they check your documents before submitting, and their support team is super responsive if anything comes up. They do charge a service fee on top of the government fee, but for a trip like Rio it’s worth having the extra peace of mind. 
The official portal works too if you want to save the extra cost, just be prepared for it being a bit slower.
Either way, with 3 months to go you’re in a good position. Just don’t leave it until the last few weeks. Have the best time in Rio!