I was successful in getting the 100k match via phone, though I got heckled first a bit by the MR rep about all the bonuses she saw I've received on my MR account the last 6 months from various offers, and so she did it with reluctance and had to 'check with a supervisor' first. Might be a good idea to start with a clean slate next time (closing all MR based cards to close my MR account and generate a new one next time), though I am not sure if or how easily they can look back at prior MR accounts too...
I do think the Skymiles 50% bonus is the best deal going for converting these MR points to cash if you can get AMEX gift cards at the best redemption rates. I just converted 100k MR points into $1400 in AMEX gift cards.