Those are nice little machines capable of surprisingly good performance for what they are. Basically it's an updated and improved version of the good ol' TC-366. They added the nice F&F heads, improved the electronics, turned the VU meters the right way around and lit them, added built in reel locks, an output volume control, improved the looks (IMO) with the nice black finish and added a few other nice features that really improve an already good entry level deck.
I really like the auto shut off mechanism in this series of simple little decks too, also like that the machine can be flipped 180 degrees in the slanted cabinet so it can be used laying back at an angle or standing up. Sony did a lot with a little on that model, they're usually pretty reliable too.
The motor run capacitor is pretty much guaranteed to go bad and make the motor slow down and eventually stop (fixed soooo many of those in all models of single motor Sony decks). The capstan idler wheel is usually in need of reconditioning too, and of course that damn grease that turns into glue.
You might want to hit the record slider switches a few more times and exercise the heck out of them, sometimes it takes a few attempts to get them to wake up. Usually they are the cause of recording / playback amp problems in these machines, the electronics are actually very reliable even after all these years (which is good because the amp boards in these are a huge PITA to work on!).
Congrats, they are fun little machines. Always good to keep one around IMO!