Unless you know you hate a flavour (I hate mushroom and chilli) then I suggest you try all of the packs, you never know which ones you'll like.
to me, the banana was nice to begin with, then after a few weeks I went off it completely. went off the strawberry one the week after. hated vanilla from the off, tasted like cold porridge to me. only tried the veg and the chicken soup, hated both of them too.
Now I like the choc shake, and all of the bars (even the lemon one which everyone else seems to despise!)
Your tastes do change, and I reckon that if I tried most of them again now, I'd probably like them again (the strawberry one, I know I'd like now) but I figure that my 3chocs and 1bar work, and have done for over a month now, so I'll just stick to that!
Try them all, find the ones you like, and stick with it, routine will help you through, it's great not having to think about what flavour to have each "meal" time
