I have owned a S & W 686 in the past and have a Tracker SS with a 4" barrel now. To tell you the truth, I like the Taurus better. Me and the wife shoot it every weekend and have put many different loads (factory) thru it without fail. I have no problems recommending this weapon to anyone. The polymer series of semi autos, now thats a different story.
As far as using it for home defense, depends on your living conditions. If you live in an apartment then you need to worry about shooting thru walls with the .357. Even more so if you live in a house with kids at home. Also, the porting in the Tracker may cause a little flash blindness in darkness. Even though a .357 will flash alot anyway the porting adds to sight recovery problems in darkness. Maybe you might want to use .38 in the .357 pistol for home defense.
Either way, both guns are a good choice. Dont be afraid to give the Taurus revolver line a try, you wont be disappointed.