That clunky, mildew-trapping shower curtain or framed door goes away, and suddenly the whole bathroom feels twice as big and lets in all the light. The actual installation only takes a few hours, but you want to schedule it during the winter slow months when contractors are looking for work and more flexible on pricing.
Before you commit to anyone, get at least three quotes from local glass shops. Prices swing wildly for the exact same tempered glass and hardware, and having competing numbers keeps the bids honest.
Remember that the 0% intro window is a hard deadline and not free money, so if you still have a balance left when those 18 months are up, deferred interest or standard rates will kick in on what you owe.