Thanks for posting this.
I have a similar manfrotto setup. Not the same model numbers, but very close in function to what you have. I think mine is an earlier model.
I had either forgotten about (or never knew about) the center post horizontal feature. Sure enough- it's been right there on my tripod all along.
There was one point in my past where I could have used that!!!
As I remember this tripod, it's not the lightest out there, but it has been fairly stable for what I have used it for. For all but my largest lenses, it is rock solid. Even with the heavy telephoto, the tripod is adequate (using a different gimball). The price point made it a no brainer for me. The quick releases on the legs have been a godsend on uneven surfaces- and have held up flawlessly.
Overall, it's been a really good setup at a reasonable price. Unless a better setup came up at a yard sale/ pawn shop at an unreasonably better bargain (ie- the seller didn't know what they had)- I could not improve upon it.
Enjoy!