It's not really just mv its the whole of minecraft sometimes and I'm pretty sure this server has the best ram thing or what ever and they are always trying to find ways to reduce the lag as much as possible
We fixed the huge lag spikes on op prison and we made some changes to some plugins to reduce latency on all of the servers(such as, you have to be on a lobby server to change/select a pet - this was causing most of the lag spikes before). There may be other small occasional lag spikes that happen with some plugins every now and then(which we are looking to fix), though for the most part, all of the servers have plenty of ram, ran on the fastest processor with an SSD, and the instances are never overloaded. 400-1k ping may be more so your internet connection rather than the server itself. My internet is basic, and even being pretty far away from the servers(they're hosted on the west coast of the U.S, I live on the east) i'm always in between 90-120ms.
A lot of people have been lagging recently normally occuring in pvp. On OPFactions if more than like 8 people are pvping at spawn the whole server freezes. My ping has been dreadful over the past few days and many people I know have been having the same problem. Usually I get 350-400 ping but recently it's been ranging from 600-800 ping. Nothing wrong with my internet the server has just been getting laggier and laggier over time.
Your ping has nothing to do with the lag. You can't get better ping unless you move closer to the server's location Ping - How fast packets are sent to the server (How long it takes to register hits/block placement) Lag - Lag is how much fps you get, and that all depends on your computer's components