I have used a lot of Ektar 25 in both 35mm and 120 format. It has been discontiued for quite a while now. Royal Gold 25 was the same film. I naturally gravitate to the slow speed films in both color and b&w. In my opinion, Konica Impresa 50 is a far superior film in that the contrast is low to moderate. It is less likely to have cross over. The grain and the resolving power give Ektar 25 a real run for the money. It offers very nice discrimination of hues. I tend to think of Impresa 50 as being the film Ektar 25 should have been.
Unfortunately this film has also been discontinued but much more recently.
If you want a very good 35mm color negative film, I would try to see if you can still find this film as being available.