It really depends on your market, consider the price point of the house, etc. What size is the house? What does your competition have? Subway tile isn't necessarily the cheapest option, you might want to look at some of the larger porcelain tiles, etc. However; unless you are experienced at doing tile, you might want to get someone to give you a bid. Be sure to check references, licensing and see photos.
I'd avoid the tile unless you're absolutely sure you can find the right guy to do it. I do my own tile surrounds, so I'm not going to bore you with a load of information on the subject, but doing really good shower tile work isn't easy and there are more guys who say they can do it well than can actually do it. Many will quietly take shortcuts that will limit the life of your shower surround to save themselves work or because they simply don't know any better.
If you do go with the tile, here's one tip: if you see your guys hauling green drywall into your house to install in the shower, get rid of them immediately, no matter what they say about "waterproof gypsum" products.
I prefer tile over fiberglass, but have used both. Personally I do 95% of my own tile work, as well as all the waterproofing, cement board, etc. if I was paying for this work I would specify exactly how I wanted the contractor to do it and make sure he did it that way.
Thanks fork all of this feedback. It's very informative.
As a rental-fiberglass, water proof.
As an owner occupied -Subway tile. Will leak over time.
In my own house, we renovated the bathroom about 4 years ago and used a 16x16 ceramic tile. It looks good as a surround around the tub and doesn't take much effort to clean (not having the small grout lines a subway surround would have).