First, I don't own and haven't used the MFJ - so I can't comment on it. Second, I have no connection to LDG other than I use and like their products. That said, I really love my LDG Z-11 Pro with my FT-897d. Some of the positives:
1. Can run a long time (year +) on 8 AA's mounted inside the case! Great for portable/mobile use.
2. Selectable modes: Autotune, semiauto, manual touch-up, and Hi Z/Low Z antennas
3. Selectable SWR threshold for autotune
4. LED displays SWR when transmitting.
4. Unique memory setup that in conjunction with the LDG DTS-4 coax switch lets you run 4 seperate HF antennas with autotune for each one. The Z-11 Pro has 8000 seperate memory slots arranged in 4 banks. Within each bank, each of the 2000 slots is associated with a given frequency range. Thus one frequency can have 4 different L-C solutions. When automatically tuning, the Z-11 Pro senses the frequency, associates it with the appropriate 4
slots, tests all 4 stored memory contents against the preselected SWR threshold and automatically selects the best match to whatever is on the port - faster than you can blink an eye. If no match, it goes into tune mode and generally matches in less than a few seconds. The beauty of this 3-D memory is that it in effect remembers not only the frequency but the associated antenna! Couple it with an LDG DTS-4 coax switch, and it's like having a seperate auto tuner for each antenna. This was a MAJOR factor in my choosing the Z-11 Pro. Awesome technology elegantly executed.
There is a great explanation of this on W4RT Electronics at http://www.w4wb.com/index.htm
Look at Block 4 - Frequency-Sensing Memory Tune.
5. Will tune all types - verticals, dipoles, beams, and long wires or ladder fed(with a balun).
6. Support from Dwayne Kincaid at LDG that is unbeatable!
My only negative - sounds like a blender with ice cubes while it does the initial tune! But I just think "margaritas!" and the noise is done before I know it!
You can download the manual from http://www.ldgelectronics.com/c/261/product-manuals
If it meets your power out range, the Z-11 Pro is my vote. It does "Get her done!"
Rick - AI4LG