The purpose of the MAF screen(and this topic has been beaten to death) is to provide a laminar airflow across the MAF sensor/sensors. Or in english, it takes the turbulence out of the air.

Does it really work as promised ? Or is it laminar snake oil..LOL!
I guess the real question should be will I suffer any ill effects if I leave it out ?

Talking about snake oil..
I think I need a drink ! LOL !

Yes, the MAF sensor depends on the MAF screen. The sensor has to see the air moving across the sensors to determine how much air is entering the engine and how much fuel to dump. It'* all mathematical in the programming as I have seen in HPTuners.

Mike you truly are a wealth of information.
Ok.. oh wow..I guess it has to stay clean (stock) and stay installed then.
So I guess If you CAI things you then are best to chip-reprogram and leave screen in ?

Chips are worthless. They just fool the PCM into thinking something else.

A CAI won't have much effect with the MAF sensor. But you can tune the PCM to make better use of the CAI.

Would I gain any extra MPG with tuned PCM w/ CAI and more free flow singular muffler then?

cai i would guess isnt going to make a difference in the rpm and throttle range that you are using to get the best mileage. they can lean out your a/f to get you better mileage as well as mess with shift points to short shift and keep the tc locked, the best value is a k&n drop in when you consider cleaning it instead of buying new it pays for itself eventually so mileage is bonus. my 98 bonnie got about 2 more.

as far as exhaust the cat is the choke point so if you are leaving that it doesnt make much difference whats behind it. unless its a extraordinarily restrictive pipes or muffler

Ya 10-4 Justin thanks. Just every time I hear K&N air filter, I wonder how much particulate matter is getting past into intake.
I may try a K&N anyways...anything to improve gas mileage is good!
I know in the future this muffler is going to need a replacement. Kinda sounds a bit thin in there and well rusted towards the center, but not all the way through..yet...
Cat still looks good..sure don't want to replace it!

Before I comment on this I'll say I'd leave the TB screen in, as Mike said that topic has been beaten to death, I have seen debates on it on a few forums, most lean towards suggesting it be left in, at least from what I have read.

IMO I'd only consider the K&N filter if you go with a CAI setup, that way at least the filter is a bit further downwind of the MAF, I do believe the particulate matter you speak of can contaminate the MAF, more so if you have a lot of humid/rainy weather.
My car ran fine for years without me ever cleaning the MAF, but within two years of using the K&N filter my MAF was reading a bit off, it was not off by much, but enough to cause misfires at idle.
I tried cleaning the MAF with MAF cleaner to no avail, and even carefully used carb cleaner on the thermistors, that did not help either.
So I went with a new MAF, and a Purolator Premium Plus Air Filter, and have had no issues since.
I cannot say for sure the MAF was ruined by the oil particulates, I know I never over oiled it..
My MAF may have just failed coincidentally, but I still recommend not going with the K&N unless you go with a CAI, and even then be sure to clean the MAF each time you clean/re-oil the filter.