The silt striders were, to me, an essential part of the Elder Scrolls experience. Being able to just instant-travel takes away incentive to explore and ultimately makes the world feel less lived in and interactive. I loved the way you could hear them trumpeting from time to time in the major cities, and that if you killed a silt strider pilot, you would have no access to the silt strider network from that location anymore. It was great.
Sure, people would ***** about taking away fast travel, but when it comes down to it, exploration and travel limitations are an integral part of the RPG experience. It's like having to wait a while for a well-cooked steak; People think it would be great to get it right away, but if you actually give people that option, I think they would realize they miss the hour or so of conversation and anticipation that comes before it.