Pretty much everything you need is in Fl Studio. The only reason I use some other plugins like plug ins from Izotope Ozone is because they either give me more options or let me do something different.
For example: If you use the Fl Studio Parametric EQ 2 you have everything you need, so typically I use those that EQ on most things. However the Izotope Ozone EQ allows you to do something that he Fl Studio EQ's cannot. Which is, it allows you to "Solo" frequencies so you are only hearing what area is "solo'd".
And the plus to that is, I can hear the frequencies that sound horrible since that particular EQ gives me the option to solo areas in the EQ plugin.
They both pretty much do the same thing, its more of what they offer. Some plugins allow you to do more things.
It also comes down to what your used to using and know what to use.
There are certain plug in's on Fl Studio that I am used to using so I perfer it and other plugins eat my CPU up when I open them.
There are certain plug in's on Fl Studio I don't use for mastering compared to other programs because it doesn't let me fine tune what I need.
Where other plugins give me more of a fine tune option.
To explain what I mean by that: There are some plug ins in Fl Studio that only let you set "points" at certain DB locations which is annoying.
What that means is. Lets say I wanted to put a point at -16 Db exactly.
Some plugins only let you move the points up and down by like every 5 or 10 DB, meaning you would be forced to use -15db because it does not let you go down -1 db at a time and instead you have to move up and down by +5 or -5db which is annoying.
Either that or I simply did not figure out how to change that option in the plugin.
Which is why I will use different plug ins that allow me to pick the EXACT DB I want to place points at.
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Really what it comes down to is messing around with the plug ins and getting other plugins to compare them.
Most plug ins are perfectly fine in Fl Studio.
The EQ 2 is fine
The Fruity Limiter is fine and in fact I like it better than other plug ins because I can VISUALLY see what I am compressing and where to compress
The Fruity multiband is fine
Maximus allows you to do alot of things however I don't use Maximus as a main mastering plug in.
Its personal preference
For me, I like plug ins that are "Visual", I like to visually see where I am effecting my music so I can understand it in my brain while listening to it.
Some plug ins you have to use nothing but your ears, and while some may prefer that, to me its just faster to visually see where you need to compress and start from there and make adjust ments.
The best analogy I can use is this
If you had no eye sight your sense of hearing would be increased
You can hear a chain saw really well (I mean I hope so, its a damn chain saw)
But if you were able to see the chain saw while hearing it, you could "see" how far it is away which will allow you to confirm how far away your brain is saying your hearing it.
Stupid analogy but my point is, I like the visual plug ins because they help confirm what I am hearing and make my work faster to get through.
The only plug in that I don't like for mastering is Maximus. Literally every other Fl Studio Plug in I use for most of the mixing, then I typically use other plug ins to master.
I am not saying I do not use maximus for anything, I am saying I don't like it because its not allowing me to do what I want I am trying to do, unless I am mistakenly missing something.
My example of what I mean: In Maximus you can place "points" on the compression curve. Well for as long as I was messing with Maximus, it only allows you to place points every so many DB.
So pretty much Maximus will allow you to place points at like -5db, -14.5 db, -18.db, -24db, - 33db.
So if you try to place a point at any db in between those points it will NOT allow you to place a point in between those numbers but will instead move your point whichever one of those db's is closest.
Not sure if maximus is set up like that or if there is an option to select your exact point, if so I would use maximus more often.
However because I could not figure out how to get an EXACT db point, I'll just use something else instead like a different multi band compressor that lets me choose my own EXACT points.
I basically don't use plug ins unless they let me do EXACTLY what I want to do and let me choose EXACT db points.
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Thats just my opinion though and what I like.
To answer your question.
Yes, Fl Studio has pretty much everything you need. However some plug ins are strange to figure out and took me a while to figure out how to use some of them because they were not set up easily to understand. For example, the EQ 2 is easy to understand. The Fruity Limiter is easy to understand. The fruity multiband compressor took me a while to figure out, because I already knew how compression works and what it sounds like, I just counldn't figure out how to solo the freaking bands based on how the plug in was set up.
In Ozone you simply press the "S" button and it solo's bands, its easy to understand.
In the Fruity Multi band Compressor it took me a good 15+ minutes just to figure out how to solo a band because its set up confusing compared to what I was used to seeing in Ozone.
