Wow, I am just so impressed with this selection of products - really high quality! I got this set right before my long trip to the Philippines - I was concerned about being in that dry airplane air for so long and I wanted something easy to pack for the hotel. I looked around at other stores, but I couldn't find a set that is both vegan and not crazy expensive.
The volume (of each product and combined) meets the airline carry-on standards and the bag is so slim it fit in my carry-on bag pocket (easy to take in and out on the plane). I used all, but the cleanser on the actual plane to keep my skin hydrated and refreshed (I brought cleansing wipes for the plane). The Oxygen Gel felt especially good.
I like that all the products are either unscented or minimally-scented. I think just the cleaner has a scent and it is a very mild almond scent. I didn't want to offend anyone on the plane with strong smells!
Each product is great on its own, but I think they're even better when used together. The Oxygen Silk Gel layers nicely with the MSM moisture serum, then depending whether it's morning or night I use the Alpha Hydroxy Night Cream or the Titanium Sunscreen. Unlike other sunscreens, this one feels really nice as a base under foundation. It's not greasy and absorbs completely in the skin, so it didn't make my foundation messy or streaky. Not sure I'd wear the sunscreen on its own (without additional sunscreen in my foundation), but it's awesome as a light-weight base layer.
Anyway, this review is REALLY long, but hopefully it's helpful!