The studio line brushes and the HD blushes. It's really a tie between the two. the brushes because for $3 a piece they are some if not the best brushes that I own. The HD blushes because they are VERY pigmented and a little goes a long way so they last long and all the colors are great.
Definitely Studio Lip Balm SPF 15, love love LOVE this stuff. it does have a bit of a smell but it's so easy to get past it. very very moisturizing, definitely my HG lip product! i have it in nude, gives great tint. trying newer colors soon.