Gotta say, after making 1K on UA that I'm surprised at how much more useful the status is than after I made SEN on LH. A bit of background:

In 2008 I would fly, in Y, TLV-FRA(or ZRH)-JFK or SFO about every other month at least. I'd use UA for domestic connections. Didn't take me long to hit FTL, which I liked a lot given it was a low threshold and gave me lounge access. Also didn't take too long to make SEN. I was op-up'd once, and got one award ticket in C.

My base changed to JFK in 2009, and I made monthly trips from JFK-SFO and many LGA-ORD jaunts (as well as a bunch of other irregular trips). Not too much int'l, but I went TATL twice on LX and flew with my SEN (100k) status. I got to book exit row, and was greeted on the plane, but other than that had no advantage over just using my UA status.

As a lowly 1P, I found it super easy to upgrade my JFK-SFO P.S. flights, and flew 50% of my legs in C (I only upgraded on the way out since it's the longer leg). Upon making 1K, I booked my honeymoon trip to BKK all in C with a combination of miles for 1 award ticket and SWUs for a ticket I bought in Y. It was painless. I still have 4 SWUs left for the year, 8 CR-1s, and now with UDU I know I'll be flying a lot in C (via CR-1s and miles) or F (UDUs) given my routes.

M&M gives you 2 eVouchers for making SEN status, that's it. 2 eVouchers are enough to upgrade a FRA-JFK leg, for instance. Compare this to 6 SWUs for making 1K...not even in the same ballpark. The only mitigating factor I can see is that LH's C is generally better than UA's old C, but with new C on 747s/67s and coming soon to 777s, I don't see the advantage as much anymore.

Summary: Seems to me that if you're flying to/from Europe in C or F, LH/LX M&M might be your program. They do things "above and beyond" like limo transfers etc. that UA doesn't and will never do. But for just flying a whole bunch in Y, I can't see how M&M holds a candle to UA at its highest elite levels.

Any other 1K/SENs out there who can weigh in?