Exante and other VLCDs bought online are cheaper, yes, but they have less variety when it comes to flavours and they don't do the wonderful Tetra packs. Apart from this, they don't offer a one-to-one consultation every week. My friend is one of those people who needs structure; she needs to feel 'accountable' when dieting. She did fairly well previously on WW and SW because of the weekly meetings and weigh-ins. The only problem was the slowness of the losses. She has never yet missed one of her CD weigh-ins.
For those who can just get products delivered and then get on with it, the cheaper versions are fine, I'd say. But a lot of people can't. When you have a month's supply of packs and bars sitting in a box, and the month yawns ahead, full of temptation... lol. It can be tough!
I myself am not a 'slimming club' type person and would hate to be tied to a weekly meeting/group of any kind but I have to admit that the regular weigh-ins and chats with my CDC, did help me a lot.
In the end we have to go with what we can afford, counterbalanced with whether or not we can stick to unsupervised VLCD-ing. If not then we may end up paying out more to lose weight over a longer period of time.