I have not used whizlabs. But as far as i know javaranch members used to mention the level of toughness in increasing order as below and i confirm that it is true in case of 2 and 3.
1) Whizlabs.
2) Real SCJP exam.
3) Devaka Cooray.
Saravanan Thoppae wrote:level of toughness in increasing order as below and i confirm that it is true in case of 2 and 3.
1) Whizlabs.
2) Real SCJP exam.
3) Devaka Cooray.