you are doing the software updates correctly, as is evidenced by your lack of problems.
Updating the OS, as and when Apple release an update, is fine.
Combo updaters are generally used when you do an Archive and Install of the OS. The initial install only puts the version of the OS that is on the installation disk. This is invariably many updates behind the current version and instead of using each individual updater to bring the OS up to date, the Combo updater is used. It even appears in the Software Updater window as the method of choice.
Hope this helps
P
I have been doing it incrementally via software update and so far have had no issues. The more i learn about mac it seems that the majority consensus is to update via the larger combo update. I hope i am not beating a dead horse with this question but, is that what i should have been doing all along even though i have not had any problems to my knowledge?

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