We mulled it over for all of five minutes...we only added on 50 points, so we couldn't take advantage of the offer, but we figure that the 50 points will make a difference so that we can get a two-bedroom with ease (so we can take my mother...). If my job wasn't in jeopardy, we might have considered the 100, but we figured we could definitely swing the 50 (since my mum is so kindly bribing us by paying so she can come!!!). We also were able to get our use year, so there won't be any confusion in banking points in the future!
Our rep, Tony, was wonderful - didn't try to pressure us into more points at all. I assume that they are getting plenty of requests.
Good luck!