I haven't, but I'm still under a 2-year price guarantee until later this year so maybe that's why.
If they sent me this offer, I would pass because I'm happy with what I pay and the speeds I get (even though I got in too late to get 35/35). This is certainly an incentive to get people on the new pricing plans but at least they're using the carrot of "here, have a free shiny" instead of the stick of "guess what, you're going to whatever rate we have now and you'll like it." I'm not opposed to a little bribery from my telco.