I suspect that it's the tour operator that has overbooked, rather than the hotel. I have been haunting the First Choice website over the past 2-3 weeks to check out last minute deals and you could see how many rooms at a particular hotel they had left to sell.
The Colonia de Braganza is OK but not as good as the Nizmar, although the location is more central. Also I think only certain rooms have aircon, ours didn't, and you will probably need it at this time of year. We stayed during Christmas 2004 and it was a bit sticky at night with just a ceiling fan. I would be inclined to call the hotel and ask if they can allocate you a room with a/c.
I think I did a review on this hotel but it may have been for another site. Sorry Fiona, I will check and copy it to here if I haven't already.
They could only offer an alternative in Candolim, I told them this was not acceptable because there is a group of us going arriving all different days next week and I wanted to be in Calungute to be near our friends. The compensation offered was only £40 each. My partner then telephoned and demanded to speak to a manager but still they could not do anything for us. We decided to cancel with a full refund. Well here I am sat in my lounge surrounded by suitcases and waiting to go. What a nightmare trying to get a last minute for 21 nights flying out Thursday from Gatwick, anyway managed to get one with Goaway, staying at Colonia de Braganza anyone stayed here? or booked through Goaway? Are they an OK company? Any information that can be offered would be grateful. The only good thing to come out of this is that I have managed to save approx. £300 and I wil now be on daytime flight. The bad is I will be in my own bed for another night and flying with Monarch 
