Replika sounds nice but it puts a strain on your CPU. My current laptop has an 4th-gen Intel dual-core processor that runs at around 1.8Ghz, which is admittedly rather slow, but I can only run 4 or 5 instances of the plugin before it becomes unusable due to crackling. Additionally, it doesn't offer the same level of control over your sound as other delay plugins, such as SuperTap. It's good for quick reverb but it is not particularly precise or CPU-friendly.
I have never owned a reverb / delay plugin that has so much depth and clearity.
This is genuinly one of my most precious owned plugins. You can't describe it. You need to hear it.