I switched to it about a year ago to get rid of Google Analytics. Quite happy with the decision.
Where are you hosting it and how much do you pay for it? Do you have a lot of visitors?
If we're talking about 10s of thousands, you're gonna need to invest in some SSD (€50-70/month probably).
If we're talking about dozens of sites, some of which have millions of yearly visitors (and a bunch of plugins and reports that need to be generated), then you're gonna encounter some issues and have to spend a considerable amount of time optimizing every part of it, and hardware cost will rise to a hundred or two per month.