Jack,

In the 915F, the 13.5 & 15 degree lofts are both 3 woods, while the 16.5 degree loft is probably more like a 4 wood and the 18 degree loft is more like a traditional 5 wood.  My suggestion is to locate a qualified Titleist fitter in your area  and have him/her fit you with the correct head & shaft combo that is best for your game.

Best of luck with finding the correct fairway woods for your game.

 Totally agree, go see a fitter.  I only carry one fairway and the rest hybrids.  Best decision I made was seeing my fitter. The Titleist hybrids are really long and accurate.  My 17* 913h which is set up at 16.25* I can hit past most of the seniors I play with off the tee box and they are hitting drivers.  Go see the professional and let him set you up with something designed for your game. Only advise.

There are many options to the 915f, I would recommend going through a fitting as the 3 wood ranges from 13.5* - 16.5* and 5 wood could range from 18* - 21*. Also you may like the hybrid instead of a 5 wood?? A certified fitter or PGA Pro will be able to get you on the correct path for your game.

Always good to listen to advice of your friends, not that you should take it. The "standard" setup has traditionally been the 3W/5W. However, many golfers have difficulty with a 3W getting enough loft and can do as well or better with a hybrid instead of a 5W. In your set of irons you might need some help with the 3/4 irons to be able to launch them. What will help you best would be to check your irons and fill in the distance gaps to driver with whatever combination of hybrids and fairways to complete a set that matches your game. In my own experience, I get my best advice from an on course professional fitter. Large box stores tend to promote products in stock and dissuade custom options that don't cost anymore. In some cases, they won't even offer a LH version readily available from Titleist. Have fun getting into golf and hope you get the right tools to get the most.