You really have to know your team in order to succeed with these sliders. I was using the 97-98 rosters, and I managed to beat the 76ers using the Lakers with extreme ease. Then, I tried playing against the Knicks using the Jazz, and I was in the process of getting blown out of the gym halfway through the second quarter before I rage quit.
I don't know how to be successful with the Jazz, but I grew up as a Lakers fan, so I felt right at home. There's also the fact that the Knicks were great back then, with Ewing et co.
The sliders can feel downright cheap if you don't know what you're doing, but it's all about strategy. You need to mess with every aspect of your defensive settings and your coach profile, as well as determine who you're going to run the offense through and who the shooters will be.