The simulations cover the same material as the MCQs, just don't give you multiple options. So if you understand the MCQs well, and could come up with an answer before reading the problem, you'll be alright. And…some portions of the SIMs are still somewhat multiple-choice…like if you're doing a SIM involving depreciation, then it will have you create the journal entries for the depreciation, and it will give you a drop-down list of account names – “Accumulated Depreciation”, “Depreciation Expense”, “Fixed Assets”, etc. If you end up using 4 account names, there will probably be 5 or 6 in the list, so it's not just “Put one name in each open spot”, you do have to pick a bit. So, the only part you're doing totally on your own without multiple choices is the computations – you'll figure (in this example) the amount of depreciation under the specified method, and won't have choices to compare against. But…so what? If you know how to figure depreciation, then you could do the exact same work in a problem that said to select the amount by which Accumulated Depreciation changed in Year 5, and gave you a listing of credits and debits to select from. You've still got to do the math, still have to know if it's a credit or debit. The big thing with the SIMs is that they count for so much more than each MCQ!
So in my mind, your best preparation for the SIMs is a solid understanding of the MCQs, and more specifically of the concepts behind them. There's no different material, just a different presentation. Becker's might be easier than the “real deal”, I don't know, cause I haven't used Becker…but if you understand the concepts presented in the lectures, you'll be fine.
.