downpipe and turbo questions, which to get? Options

[Rollout]

Well it seems as though no one on DSMtuners.com is willing to tackle my questions, so possibly some of u dsm'ers can help me out. Thanks A LOT.
Heres my post:

take all this into consideration when evalutating...
I have a 97 Eclipse GSX with upper and lower i/c piping (greddy), Greddy type-s bov, K&N intake, Apexi N1 catback, walbro 255

ok, at the moment i am looking at finishing off my exhaust system. I already have the Apexi N1 cat back and need to get a downpipe. In the future i plan to upgrade to the big 16g or the evo III b16g. here are my questions.

1. RNR 02 eliminator downpipe in SS is $440 on rnrracing.com, or i can get an evo III O2 housing (does this bolt right on?) for $190 and a apexi downpipe for $207 - thats $397 together, or i can just port my stock O2 housing (id like specifics on how well this works?) and get the Apexi downpipe also. This is all 3" and the downpipes will "remove" the cat.

what are your suggestions?

2. Which turbo? Price differences are minimal (around 500 i think?) but what are the real differences? the Big 16g i know requires a $200 kit for the 2g, im not exactly sure what the evo III b16g requires? i know that the evo has a bigger wheel but thats about it, so more lag, but more power?

thats about it for now... thanks in advance, i know a lot of questions
just dont want to order the wrong thing here.

[Rollout]

whoops, what i ment by the $500 is that they are both around the same price, which is about $500 where ever u look, that doesnt include the $200 kit that u need for the 2g's. both turbos need that kit i guess. So it seems to me the evoIII is the better turbo here and about the same price?

as far as the downpipes go... u think the RNR is better quality then the apexi downpipe + the OEM lancer O2 senser housing? i know that the apexi and rnr downpipes are 3", but im not sure what size the evo O2 housing and the O2 eliminator are, so im really not sure which is better. I think the stock O2 housing is 2.25? or maybe thats about the size after you port it... im not really sure.