My Atlas is my only milling machine presently, and it's a work in progress. Sitting in the airport and on the plane I made notes from memory of what I need to do when I get back home. I mostly use it as a horizontal mill, using endmills held in collets. I hove a bodged up vertical head made from a Taig lathe spindle, and a pattern started for casting a new vertical spindle housing out of aluminum (maybe cast iron later), just need to get a couple more patterns made to justify firing up the foundry.
I use a DC motor and treadmill speed control to run the horizontal spindle. It's nice to dial in the speed, especially since I lack the original reduction pulleys. I intend to keep that arrangement, but will reproduce the necessary pieces for the backgear after I get back. I have a few tasks that require it.
It's an extremely capable machine, and can take surprisingly heavy cuts for its size and weight. With that said, remember that it isn't a big old Bridgeport.
Add a dividing or indexing head and tailstock, and it's a very nice machine for making gears, splines, etc. I recommend a couple of sets of 1-2-3 blocks, v-blocks, machinsts jacks, and a well stocked clamping kit. Some angle plates are also handy to have as well. If you have the capability to make one, a tooling plate is really nice to have (its on my to-do list) as the single t-slot can cause some "creative" clamping problems at times.
They're solid little machines, well suited for second operation tasks, MT2 tooling is inexpensive, and if well maintained and adjusted, accurate little buggers.
Just remember - *NEVER* climb mill on that machine. Ever. It will snatch the table, jam the cutter, and sometimes fling the workpiece out. I don't even climb mill a finishing cut of a thou or two with mine, because it did exactly as above. Ruined a nearly finished workpiece.
I think you'll like that machine.
