Ektar 100 is a great film, and I have had good results from both Dwains photo, and Milford Photo with 120 format when I had it processed and scanned by both of these places.
Something I have not had good luck with when using Ektar 100 is scanning myself. I don't know what equipment you have, but if your thinking flatbed scanner at home think again. Let the people that do it all the time and have the right equipment that gets calibrated regularly scan this film for you. Having the lab scan the film is only a few dollars and we are talking about a handful of rolls that you will only be shooting for this once in a lifetime event. If you don't like the lab's scans you can always scan yourself, but once you get your film from the lab it is a lot harder to get them to scan it.