Some are worse than others, but there is latency across all the new servers. There was a correlation to the number of records in msrepl_commans and performance. But even when we set ImmediateSync to 0 and running the Distribution Cleanup job every 30 mins to keep the table size, this didn't help with I guess suggests it is an issue with applying the commands at the subscriber rather than getting the off the distributor?

There is no latency on the 2000 boxes