The sink is always better choice than sourcing.
Then N-channel MosFets along with NPN transistors are much better than P equivalent ones and more choices available.
And finally, even if a PIC can source or sink 20, 30 or 50mA per pin, there is a maximum TOTAL dissipation for the whole chip, so that you cannot source at the same time on all pins a max of 50mA on each pin!
You will melt the chip!
So, yes. I am for the sink topology too.
Ioannis
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