I have my wideband o2 in my test pipe, and honestly, there is a very slight delay, BUT mostly at very low rpm or at idle. I've noticed that when running closed loop at idle off of the wideband, the MS will hunt for the right A/F back and forth. This is even with 16 ignition events per step, 1% step size. Off idle and off of low rpm, its just fine. If its at all possible, i would really put it where the stock front o2 sensor goes. It shouldn't get too hot there, and will provide super fast readings during closed loop control of the MS.

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)