I'm in the BMI camp as well mainly because of the large percentage of Hamptons I stay at, but also because I don't feel the need to matress-hop just to maximize mileage earning (though sometimes I still do so to maximize stays). In just 2 months I'm up to 10k BMI miles, enough for a round-trip in Europe. I'll likely let those miles keep building (at around 50-60k/yr) for use for either TATL on BMI or somewhere else in *A.

The only time I switch back to DL SkyMiles is when there are significant bonus miles or MQM promos. I'm doing DL right now on 2-night+ stays for the 1k MQM promo. 1 night stays are going back to BMI.

Before I found the BMI deal I was doing DL Fixed Miles at Hilton/Embassy/Doubletree/HGI and Points+Points at Hampton/Homewood. I was also doing alot of matress hopping to maximize mileage, but with the BMI program I don't feel the need to do so nearly as often.