Do I need the "Slim Fix V4 (Comsoft)" or any FIX for my future modded PS2Slim?

[Norhter]

Hello everybody, how are you.
Well i have a couple of questions, i just got my new PS2 Slim Version, and of course i want to mod it . I will buy the Matrix Infinity modchip, but i saw this "Slim Fix" and i was wondering if i need it, i mean: im gonna mod my console with MI, do i have to get this slim fix too?

The shop im gonna buy the MI is
http://www.modchipman.com/matrix-inf...ine******98.html

The place i saw the "Slim Fix V4 (Comsoft)" thing is located here:
http://www.modchipman.com/slim-fix-v...oft******08.html

By the way, does anybody have a good/bad experience with this online shop???

Finally, my english isn't as good as yours, so please don't laugh.

Thanx in advance.