Hey Rob,
Ok a 422 MPEG 2 file will only be created in Episode Pro (Compressor only does 420) as for the Pixel aspect you will find it hard to view back the encoded 422 MPEG file in Quicktime as the Colour spacing doesn’t allow oyu to view these files.
I recommend you download VideoSpec (free) this allows you to drop a Video file in it and this will allow you to truely see the dimensions, Quicktime is always a little shading on showing you the true dimensions.
Also Download VLC for mac as this will allow you to see the colour spacing on the MPEG file, remember that if you are delivering to a TV station you will need to follow their specifications of Video and Audio level – I usually ask them to send you a file first and judge from that …..
I worked in the world’s largest file delivery company for broadcast for many years and constantly saw loads of files coming in – issues varied from Interlacing issues, aspect ratio, No VBI, frame rate issues, title safety, audio levels etc etc.
Once you have set it up you will be ready to deliver away !!
USe Episode Pro as it is the stablemate of Telestream for MAC.
Hope this helps !
Craig