I'm working on a comparison website, so needless to say the search function is the primary feature of the site. I have two input text boxes and a search button. At the moment, the input text boxes use Ajax to query the database and show a drop-down box, but I'm wondering if it would be more intuitive to use a select box instead? The second box is dependant on the first, as when the first is selected theres another ajax query so only the available options for the first selection appear in the autocomplete box.

Autocomplete

Pros: - "Feels" right? - Looks more appealing than a select box (css design)?

Cons: - the user has to be instructed on how to use the search (made to think?) - Only really works off the bat with javascript enabled. - The user may get confused if they type in what they want and no box appears (i.e., no results)

Select Box

Pros: - Can bring up the list of options / know whats there from the outset. - We use select boxes every day (locations etc.) so we're used to how they work. (more intuitive?)

Cons: - Can look a little unaesthetic when theres too many options to choose from. I'm thinking maybe at most around 100 options for my site over time.

Any thoughts on how I could go about this would be appreciated!