I ordered three of these for a business from the seller Quality Re-Certified. I am appalled at the fact that I got three machines that were all extremely problematic.The actual build and delivery time of the computers was fine. Nothing out of the ordinary. The Optiplex is a solid piece of hardware. But when I went to set up these machines, that is where the issues came up.The machines on first boot and setup seemed fine. Clean image of W10 Pro with one exception, an install of ESET Antivirus, which is an expensive, non-standard AV/malware software and should not be installed on a factory refurbished machine without the buyer being made aware. ESET cannot be uninstalled, the services related to it cannot be stopped, and the only way to fully remove it is by performing ANOTHER fresh install of W10. My company does not use a company image, as these are just terminals that are used for remoting into other software and servers, so I typically do not image a refurb machine when I buy one. Unfortunately, I have had to do that on all three of these computers.If you do not reinstall W10, your machine will boot fine for a day or two, but then all of a sudden you will be met with boot errors and BSOD. I am confident in thinking that ESET was somehow flagging boot-related files for quarantine/deletion, removing these files without warning, and thus breaking my OS. All three of the machines I bought had this exact same issue. Once could have been understood and written off as a bad drive - sometimes, things happen and you accidentally are sent a bad hard drive. Twice is an anomaly, but could be understandable. Three out of three machines is lottery-odds lucky that they all have the exact same boot issue in the exact same amount of time.I cannot with confidence recommend the seller. The machine is fine, I like the Optiplex as a simple workstation because it does what it needs to. But the seller needs to either advertise the fact that their refurbs ship with ESET AV, double check the installs of Windows, or have a more accessible customer service line. I will not be buying from them again.As for the actual computers, they are great. The Optiplex is known for being easy to service or upgrade, and having a lot of external ports. There are 10 USB ports, support for PS/2 peripherals, multiple DisplayPort 1.2 ports, Gigabit Ethernet, and ample amounts of storage. The form factor is also great as it fits in any workspace. I do recommend changing out the HDD for two 2.5" SSDs using this mount from Corsair: https://www.amazon.com/Corsair-Dual-Mounting-Bracket-CSSD-BRKT2/dp/B016498CK0/ref=sr_1_2?crid=2RTB30W25FEWM&keywords=corsair+3.5+to+2.5&qid=1565299828&s=gateway&sprefix=corsair+3.%2Caps%2C184&sr=8-2I hate to leave poor reviews of sellers because I know that many are trying their best. But this has been unacceptable from Quality Re-Certified.