Hi Wasif,
While I can tell you that my experience with the PMPrepCast exam simulator was great and beneficial, I cannot help with the PMI practice test, as it was not available at the time.
I've read different experiences about the PMI practice test; you may want to use the search tab to look for posts about that, both in this forum and in the Lessons Learned one. Many former students shared their experiences and opinions, and I hope you will find them useful.
Gabriella