Speed/Performance and Server Requirements

[gety9]

Guys hi,

It's more a question than an issue.

1. Does using remote A/B testing server results in loss of performance/site speed comparing to solutions where A/B testing engine is directly on web site server?
   (as i understand there is a delay because we have to make calls to wasabi API hosted on different server to makes decisions about which alternatives to show to which users, and we have to wait for a response to get alternative to render the page)

Details: We have website site on php, and i am wondering if in our case it's better to use php native solution placing A/B testing engine directly on web site server.

2. If we decide to use wasabi what is the recommended server set-up?