Answers: Disadvantages:
Can be difficult to learn.
Requires multiple entries for like peas in a pod transaction.
More prone to mistakes.
Finding mistakes can take longer.
Compare to single-entry or pegboard accounting systems for citation. Single-entry is faster to learn, but offer less flexibility and mostly requires a smaller Chart of Accounts.
Basically, you are looking at a difference between using Quicken and Quickbooks (single-entry vs. double-entry).
Good luck!