Nintendo - SNES / Switch
I have yet to decide which is the best for me. Too many memories and great games on the SNES: Super Mario World, Yoshi Island, Link to the Past, Super Metroid, the first Mario Kart (oh god!), Donkey Kong Country, Final Fantasy 4-5-6, Secret of Mana, Chrono Trigger, Street Fighter 2, Rockman X, Ghoul's and Ghost, Castlevania 4 and 5, Actriser, Ganbare Goemon 1-2, Demon's Crest. The Switch is in my opinion the best Nintendo console since the SNES days.. By the end of its lifecycle it could end up first!
Sony - Playstation 1 (PSX)
The first Playstation was a total revolution that today is not so easy to understand for the newer generations.
It probably had the most incredible lineup ever with games I loved so much: Final Fantasy 7-8-9, Final Fantasy Tactics, Chrono Cross, Xenogears, Breath of Fire 3, Suikoden 2, Tekken 3, Soul Edge, Ridge Racer 1-4, Einhander, Resident Evil 2, Motor Toon GP, Gran Turismo, Crash Bandicoot, Castlevania SOTN, Metal Gear Solid. Too many much beloved series started on this platform!
Sega - Dreamcast
Although I had a lot of fun with the Megadrive and Saturn, probably was the Dreamcast the real star on the Sega side.
Played a lot of great games and Arcade perfect ports for the first time on a home console: Crazy Taxi, Daytona USA, Soul Calibur, Dead or Alive 2, Power Stone 1-2, Resident Evil Code Veronica, Sonic Adventure, Phantasy Star, Skies of Arcadia, Street Fighter Zero 3, JoJo's Beat'em Up.
Microsoft - ???
Haven't owned any Microsoft console yet.