Yes, you will see a difference in your prints, even mounted behind glass. Good fiber paper prints look so much nicer than RC paper (and they last longer, when properly handled) that they only question you will ask is why you waited so long to switch. One thing worth mentioning, too, is that fiber paper requires a little more care in the darkroom and in finishing. Fiber paper takes longer to fix properly, and they need more washing (and ideally a perma-wash/fixer remover) to rinse all the chemistry out. RC papers fix and wash very fast because the coating keeps the liquid from absorbing into the substrate. Also, RC paper dries fairly flat but fiber prints will curl while drying and need to be flattened later. So fiber printing is more work, but it's certainly worth it for superior results.
Here's my routine: I fix fiber papers for 5 or so, then my prints go into a holding tray with circulating water while I keep printing. Once I have ten or 20 prints in the holding tray, or I'm done with that session or that image or whatever, these prints go to a fixer remover bath for 3-4 minutes where they are constantly circulated/agitated by hand. Then they might go into a toning bath, or straight into the final wash for at 20 or 30 minutes. Then they get CAREFULLY squeegee'd and laid out on a drying rack.
Then, as I mentioned, once they're dry you'll need to flatten them. I weight fiber paper prints under a heavy piece of glass with a few books piled on top for a few days, or I might give them a minute or two in the heat press if I have to. Some papers curl more than others, and they will dry flatter the more water you can squeegee out of them- but be careful because it's easy to damage wet fiber prints. I've even squeegee'd off some of the emulsion on occasion! If you lay prints out face down to dry they will dry flatter than prints dried face up- but you can get marks from your drying racks in the emulsion, depending upon the surfaces, so use care and your own best judgement about how you are going to dry. Also, always make sure your drying rack screens are scrupulously clean!
Like everything else, care with your technique will make as much or more of a difference in your results than your materials. Have fun!
