AWS is great, just switch to Sao Paulo region.
There is also Locaweb.com.br which is a bit cheaper than AWS, but their service is cheap also.
There is also Locaweb.com.br which is a bit cheaper than AWS, but their service is cheap also.
For a VPS provider to be profitable in Brazil, they need to really squeeze a LOT of tenants on one machine. Data center hardware in Brazil costs ~2x what it costs in the US. Because of this Brazilian VPS providers are trying to put more virtual servers on each physical server than the companies in the US. They do this because they need to at least have prices comparable to those abroad, so people can think "Hey, hosting in Brazil is a bit more expensive, but the customer service in Portuguese makes it worth it."
Given the virtual server densities they are aiming for to be price competitive, service is going to be highly variable. You may luck out and end up on a machine with a few other virtual servers or you may end up with 25+ virtual servers.
If your market isn't solely Brazil, then your best bet for low latency is not Brazil, or even elsewhere in Latin America. You're best bet is Miami. Lots of traffic in Latam goes through Miami, even between destinations in Latam. Try to get a dedicated server or VPS there. (see: http://www.telegeography.com/assets/website/images/maps/subm... http://www.cablemap.info )
For low latency to many clients in Brazil, you want to be few hops from the PTT. (www.ptt.br).
Tell me more about the use case and I might be able to advise you on other options.
Source: I used to be the product manager for locaweb's VPS service. Email me if you have more questions. I may also be able to put you in contact with the current or former technical leads for Locaweb's VPS service.
Maybe you would have better luck finding a dedicated server/servers in Brazil.