Advice on collecting data

I would appreciate some advice.  I'm setting up PC3 for an apparel store.  I have Apparel Add-On.  Things work well where I have few options from which to select.  Some products, though, result in too many sub-products.  For example, I have a pair of pants that require three options (model, color, and waist.)  All three should be apparel-add-on options, because not all combinations are available, and I can control them well.  For each pair of pants, though, I also offer the choice of finished or unfinished hem and ask for the length of the customer's inseam.  Because of the need to show many size choices for inseam, it would result in about 9,000 subproducts. 

I know I can use custom input fields, but can this be modified to require a drop-down box instead of a text input field?  Would BTO be a viable approach for these types of products?

Thanks in advance for any help.  I'm too new to offer anyone advice, but promise to do so as I come up on the learning curve.

Hi - thanks for the feedback - It sounds like my situation requires both Apparel and BTO.  Let me explain.  The pants in my warehouse are of different models, colors, and waist sizes.  Apparel-Add-On does a great job of letting me control what's offered and returns a different SKU for each variation.  Now, regardless of the variation, I give customers the ability to have the pants hemmed or left unfinished.  If hemmed, they must provide the length they want (a number between 25 and 37 in quarter-inch increments.)  The pants in the warehouse don't care what the customers choose, as THIS modification is made after the sale.

Can BTO work seamlessly with Apparel Add On?

Thanks, Paul