I have and its been working brilliantly, I also use endomondo to track exercise and the calories burned is immediately uploaded to mfp. Ihave been doing this since end of February (after a particularly indulgent skiing hol ����). I started at 75.6 kilos and am now 59 ��������. I am 168 cm (5'6") and am now buying size 8!!! It's a fantastic way of eating as nothing is denied. I was low carbing which does get results but is restrictive.
it depends what you mean by combining...ideally you should have MFP set to maintaining, not losing, then you eat to around TDEE apart from your two 500 cal days. Is that what you're doing? That's pretty much what I did and lost 20lbs in about 12 weeks.
I have mine set to maintain. I don't tend to eat to tdee just because I'm full enough, but do eat over the 1lb loss target. I've lost 2.5 stone now in just over 2 months. The brilliant thing with this wol is that you really only have to diet 2 days a week.