Haven't used Gleim yet.
For a background, took 2017 REG/FAR/AUD/BEC Q1 (last window for old format – NTS expiring) & Q3 REG/FAR/AUD/BEC (new format – more like experimentation), studied at least 2 days each. By just reading my 2008 Becker REG textbook (never taken REG since 2008 – lost credit in 2010), got me into 50s for 2017 Q1 & Q3 actual exams.
Without breaking any AICPA rules, I would say, either Becker, Wiley & Ninja will give you a decent mark with MCQS. You'll do fine with either one of these three CPA review materials with the MCQs testlets.
However, for the SIMS, you have to know your concepts really well, read your textbook, front to back cover. With REG SIMs, you have to be imaginative. The AICPA Sample Tests & the Blueprint is a good start.
If you haven't done real experience, think of what most IRS employees, Business Law lawyers, Financial Advisors, Tax Preparers, Tax Auditors, Business Owners (Sole Proprietorships, Partnerships, C Corps. & S Corps) do, specifically in the their taxation requirements.
Imagine if you're in their shoes. For sure, you have a pretty good idea of what they do every day during work. You even use their services at least once in awhile. They might require that you have to provide them with source documents, FS, related receipts & statements, and info in order to be able to help you.
Think like a Tax Auditor, Tax/Business Lawyer, and an IRS employee and you'll do fine.
Last but not the least, if you happen to be an international candidate, like myself, make sure to be proficient with topics that you're not familiar with.
Honestly, I haven't prepared any single US tax return. I am a Filipino-Canadian, studied in Philippines(USA)/Canada(UBC) & live in Canada for almost 28 years. I know Canadian taxes well, through my (GAP-CA & DAP-UBC) professional program's tax classes. Also, I used to volunteer, preparing tax returns for ICABC & CRA's low income seniors & families, respectively. These days, just preparing taxes for family member(s), for over 25+ years.
I would say, if you like taxation, it doesn't matter if it's Canadian (CRA), American (IRS) or Philippines (BIR), with the help of available materials through the Internet, nothing is impossible, especially if you like visiting their websites, and use Google search for professional/expert advices.
So, Gleim for REG Simulations? Sure, if you got time. But if not, with Becker, Wiley or Ninja, plus being imaginative with the SIMs, and comfortable with your MCQs, you'll pass REG.
Good luck.
AUD - 49
BEC - NINJA in Training
FAR - NINJA in Training
REG - 55
Passed: AUD (75%'08/77%'17), REG (76%'09) & BLaw(77%'99); highest on FAR (63%'11/'15) & BEC (63%'11). Credit Hours: USA(PH)-BCom'85(4yr-grandfathered); UBC-(DAP'02/'19); DC-(BBA-Acctg.'22-4th yr)=over 150 hrs credits
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