Downsides to remapping controls different than mame defaults?

[markronz]

So I am coming to the point in my arcade where I have to wire up the controls.   I've been thinking about the MAME default keys as well.  I plan on having multiple emulators on my arcade, not just MAME.   I know that some other emulators are not as flexible as mame, and some might not like mapping in the "not normal" keys.   Like the Ctrl, Alt, Shift, etc...

Here is a few of what I believe are the MAME default key settings:
P1B1    L-ctrl
P1B2    L-alt
P1B3    space
P1B4    L-shift

So what I was considering doing is wiring up my buttons so that they are all set to be normal letters, numbers, and symbols, no "not normal" keys.    I have two questions pertaining to this.

1.  Is there any disadvantage to remapping, manually, all the controls in MAME?  I mean, that's what its there for right?  Along the same lines, are there benefits to keeping all the controls set to the defaults?

2.  I have a KeyWiz, and I've never used one of these before.   I understand that I can reprogram the KeyWiz outputs to be whatever I want them to be.   I've looked at the software and I understand how it works, but I just wanted to know if it's dependable?   Do your controls ever freak out and reset back to the defaults?  Or is it dependable that it will keep the keys as whatever I set them as, all the time, every time?

Thanks!

[fallacy]

It all works. No disadvantage to mapping Mame. You pretty much have to remap mame since it uses all those keys like enter, crtl, alt as main buttons.