I'm currently testing this in our lab. Have tried lipofectamine 3000, RNAiMAX, and nucleofection. RNAiMAX seems to be the best so far. Electroporation will work, but you need to use a ton of siRNA which will convolute your analyses with a host of off target effects. You can try replicating my previous experiment.

1) Reverse transfect 250k cells with 25pmol of siRNA, and plate in a 6-well.

2) 4+ biological replicates.

3) Taqman your target transcript and a matched control (e.g., something like 18S) at 24 and 96 hours

4) Make sure your probes are "best coverage"

5) Don't use GAPDH as a control, I've noticed it has highly variable CT values.