You could probably purchase a good used cabinet saw for as much or less than a new contractor saw would cost, especially if you are looking at sawstop. You alone can only tell if you really need a sawstop. If you are accident prone or you are teaching your kids to run a saw then a sawstop is probably a good idea. Most of us that have made a career out of woodworking has had to learn how to operate a saw safely without even a guard on the saw much less a saw with an automatic brake. I've been in the business for 46 years and have only seen one accident and this guy was so accident prone he shouldn't have be working with his hands at all.
Normally with used machinery you can tell just by looking at it whether it has had normal use or has been abused. As long as a machine has had reasonable care it will last. I've got machinery I use daily which I bought in 1972 and only the on/off switch needs to be repaired on one of them. The other is functionally like brand new.
I don't like Delta either. I've had a lot of issues with the quality of their equipment and way they have discontinued parts for much of their machinery. I needed parts for a planer that at the time wasn't even 10 years old and the parts were unavailable. The last straw was a grinder that only lasted two weeks. I could have taken it back but the time and gas would have cost more than the grinder was worth so I replaced it with a dollar store grinder that has lasted many years.