I've been with Regus three years now. They do 'what it says on the tin.' I'm sure they are not are the cheapest in the market, but the service is in all respects excellent, and the worldwide network is extremely useful if that is what you need. The best features are without doubt how friendly and helpful the staff are and the consistency of the product over all the centres. The recent IT upgrades (I'm talking UK) are also great, very helpful for work efficiency.
Be careful that Regus is what you need though- the one-stop shop (e.g. one monthly bill for everything) comes at a premium. If you do not need a fixed office, the Businessworld product (access in shared rooms to any centre, any time, comes free if you have a rented office with them) may be better value for you.
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