I taught the question here is what do I get for fathers day Sentinel or Provari, not what is a better vv/vw mod out there
.
Anyway to answer your question unless you are into rebuilding I would strongly suggest going with the Provari, Sentinel being a mechanical mod wont give you the satisfaction the Provari would bring when it comes to regular tank or carto, now if you are into rebuilding and you want something that would fuel your steam engine then by all means go for the Sentinel.
FINAL NOTE:Looks has nothing to do on how well a mod would preform