So much will depend on the full specs. of your AVI files. AVI is but a "wrapper," and much can be inside that. This ARTICLE will give you some background, and tips for peeking inside the wrapper.
If you Export/Share a DV-AVI to that format, the tiny bit of re-compression in Transcode will not be noticed.
If you want a totally lossless format/CODEC, look into the Lagarith Lossless.
PS - welcome to the forum!
Thanks for the reply I read both links
Im going to try the lossless codec
Once you have downloaded and installed the Lagarith Lossless CODEC, it should appear in the list of AVI (beyond the DV flavors, and others) in the Compression drop-down (the one that usually defaults to Cinepak by Radius). I'd show it to you, but I only have PrE 4, and PrE 8 has moved some things around. Still, with AVI chosen, the Compression Type drop-down should then show Lagarity. Be sure to reboot, after you install it.