My Rocktron All-Access controller served me VERY well for many, many years, but being that the new controllers offer so much more with software integration and such, I chose that I would upgrade to accommodate my AFX purchase.
I believe that you can't go wrong with any of the choices you have in the poll... all depends on what "perks" you want and what fits your needs best. The MFC is a great controller, I'm sure, but I really wanted a controller that offered the integrated LCD screens, so that put the MFC out for me and left me with the LF+ and the RMJ MM. I did a lot of research on both and loved each one for specific reasons.
The LF 12+ offers a lightweight, small-footprint controller that is beyond powerful and would have no problem controlling anything from a single AFX to an entire rack full of gear and more. From my experience with the emails, I personally got a very quick response (30 min. or less) with their "trouble ticket" system when I was inquiring about the products. The price was obviously pricey, but still cheaper than the RJM. Back in the day when the Rocktron AA came out, it was around $1K, so I was expecting to pay somewhere around that range anyways. One of the downsides I found with the LF+ was that, after watching many of his videos and such, I always felt somewhat lost in what Jeff was trying to convey in the vids. A bit over my head sometimes. I know that I'd have a large learning curve with this unit to fully use it to its maximum potential.
The RJM MM looks like a nice product as well... but for the GT, it's VERY expensive! The 10-button is also VERY expensive. The MMGT, like the LF+ offers SO much! It also can control a single AFX or an entire rig without breathing hard. Obviously also has the LCD screens (bigger than the LF, BTW) and has larger typeface fonts since they're graphic screens and not just text screens. The 10-button was too small for my liking and the large GT was too big, so I was going to go with the LF+ until the MMGT-16 was offered for the price of the 10. Then I was intrigued. I contacted RJM directly and had a few great conversations with Ron and Sherri. VERY nice people to deal with. I own one of their rack gizmo's and they went above and beyond to help me set it all up... all via phone, so the customer service is 2nd to none!
In the end... due to limited pricing, the fact that the RJM offered a 6-button across layout (which I like for my needs) and the customer service that they offer, I went with the RJM. I also like their software (for it's ease of use) as well as their vids and can relate to what is being said, rather than feeling like everything is over my head or being stated in a very misunderstood manner. I'm a musician and not a computer science engineer and frankly, have enough to deal with in learning the AFX. The last thing I need is a controller that I can't figure out as well. I may as well never try making music again and just be content fiddling with gear. Haha!
Either way, I think that you'll be set with whatever you choose. The controllers today are so powerful and deep, there's no reason to think you'll outgrow any of them anytime soon. If they fit your size requirements, options and price range, I think you'll be good with most any out there, but in speaking of the LF+ and RMJ line specifically, I think both are great and will offer you everything you need.