Well, these are some I personally enjoy and would recommend from Chefs Vapour website -
ChefsVapour Concentrates ( 30ml - £9.00)
The Donut King ( Custard / Plain donught )
Nice Cream ( Shortcake,cream,coconut )
Welsh Custard ( Custard with I believe Caramel/RY4 )
Ginger Rogers (Ginger coconut cake with butterscotch)
Mom & Pops ( 10ml £2.50 )
Blueberry Falcon ( Blueberry/ Tobacco. Strong savoury tobacco note if you like that sorta thing)
Calipitter Chow (Strong Wafer flavour with caramal and slightly mallowyness. Unusual )
Butterfly Bait (Honeyed Peach with, to my taste, a mild anise back note )
Master Baker (Mount Baker) ( 10ml - £3.20)
Sticky Buns ( Strong Maple with mild cinnanbun )
Decadent Vapour (10ml - 3.40)
Rhubarb Cuddle ( Rhubarb and Creme Anglaise )
Again, I must emphasise
I like these. Some won't. ( Many Like Blue Moo by Master Baker, a blueberry cream muffin flavour that I found quite average really with no noticable cakeyness!)
I have more reviewed on my blog, linked below, but off the top of my head these are the cream of the crop so far. I do have quite a few others to get reviewed. No doubt if I write this list again in 6 months it'll be total different!
Hope it helps anyway