Glen Ewin is a stunning estate, and the gin and wine tastings have always left me loving the estate & wanting to go back (though they do themselves out of Cellar Door sales given Dan Murphy's is often cheaper).
Sadly, the high tea leaves a lot to be desired with cold sausage rolls, Coles bun sliders, cold scones, and inattentive staff (after they've ensured they've told you 3 times you're only allowed 2 cups of tea/coffee that they only half fill) - possibly due to short staffing, which should be better rostered by management.
Given you can get bottomless tea/coffee service, attentive staff, an intimate setting, and better quality food for high teas elsewhere for less money, stick with going to Glen Ewin for the gin and wine tastings. The fig gin is amazing and the scenery is beautiful!!
Definitely worth a visit - just skip the high tea.