I was comparing it to my 800 since I only have 50-60 hours on the Manticore. My favorite and mostly used program on the 800 is Field2 since I almost exclusively hunt in old sites. My "fast food" hunt sites are ski slopes. The 900 also is faster and snappier than the 800 (upgraded processer). The 900's expanded disc numbers shows all the iron and gives a number in greater detail. Personally, I find this extremely useful as I use iron to determine the age of the site I am working. I also have found some very cool iron artifacts, so I dig lots of iron. I also dig many large signals... they all add to the story.
I haven't hunted school grounds or parks since the last century. Part of the comfort reason with the 900 is the new design. The adjustable arm rest and slight change of the handle angle makes a big difference when swinging the machine. My detecting system is different in that I take a zip tie and attach it just below the control box. Then I take a bungee system and attach it to the zip tie loop on the detector. Then I attach the bungee to a loop on top of my right shoulder and hang the machine off that. The machine also hangs off the ground while digging. See attached photo. When adjusted properly I then gently push the machine into position and sweep while gently pushing down. I cannot hold a detector normally for hours any more due to 50+ years of swinging machines. This system allows me to go all day... or until something else in my old body hollers uncle. Damn this winter...I cannot wait till I get back to my regular hunting sites.