OGR did an article on both of these not that long ago. I own both the 18005 1-700E and the 11209 Vision 700E, and both are really nice engines in their own rights.
The 18005 is definitely a great bargain nowadays, and for me has never had a problem operationally. I know that their are some that have had a faulty Baker Valve gear assembly that would jam and had to undergo rather tedious replacement processes to fix, but mine has never had that issue and has been pretty much bullet proof since I first got it for Christmas.
As for its operation characteristics, the 18005 pretty much acts like the original 1937 model and other Lionel engines of the early 90's with the big AC Pullmor motor and mechanical E-unit, so you won't see very slow prototypical creeping like on the Vision 700E with its Odyssey Speed Control. That being said, it runs very smooth and is a steady starter. It has no traction tires either compared to the Vision 700E, but it still is a good puller all in all.
Again, with the Pullmor motor and mechanical E-unit, you do need to periodically oil the brush tab (which is exposed in the cab of the engine) and the armature shaft (covered by the ash pan underneath) on the AC motor, and once in awhile replace the motor brushes, like every other Lionel engine with an AC motor.
I will say that sometimes the smoke unit works, sometimes it doesn't. It's a little flimsy at times, especially compared to the fan driven smoke of the Vision 700E, but when it works, it works.
Oh yeah, and be careful with the engine-to-tender coupling chain, because it's very fragile, compared to both the original 1937 one and the wireless drawbar of the Vision 700E. I've had to replace the connecting rings on it after my mom knocked it off one of my shelves...
