The team at HotelChamps are very responsive, helpful & knowledgeable about their products/services - I can't think of anything that we dislike from our experience with them so far! They have been super quick in responding questions or solving issues when they arise (sometimes within minutes!).
We've had some really great customer service experiences working wtihHotelsChamp over these past months too - not sure if this is typical across all brands but it's definitely something worth noting as well. Our target market consists mostly of business travellers who prefer booking directly rather than through travel agents / aggregators like Expedia etc. At present though there isn't much difference between what an AOI has compared to other channels e.g.: price comparison sites; availability checkers online reviews etc.