If you mean have a long stretch of different types of track, no it's not at all tacky, and is usually expected because having enough pieces of any one track type is probably too expensive for most players.
If you mean having multiple types in a row, say a piece of water slide, a piece of everest, then another water slide then another everest, the herky-jerky movement actually causes pauses in the transition. This causes serious lag. When I built my nine-room ride, I did this in one section, and all my testers (lovingly) commented on it. I bought some more of the same type of piece and fixed it before opening it. Went much more smoothly!