multiple grfs cause "lag" ?

[Squirtle01]

Hello my friends! I have a question here.
If i work with multiple GRFs for my client it may cause a slower loading or slower animations / freezing of the client?
How does it work?
I mean, if I make a grf for my custom prontera, other for updated items from kRO, another for updated class sprites (doram and rebellion, once these sprites are not in bRO's grf), etc it makes my loading screen slower? Or it's just foolishness? 
Thanks in advance. I hope u guys may help me in this doubt.

[Akkarin]

They're loaded one after another and overwrite existing entries, you can have up to 10 if I recall. They don't cause client lag.

[Squirtle01]

Answered for the great Akkarin! Thanks for the answer, bro.