I'm really glad you are going to try continuing to bf! Just to reassure you, BF is the best thing for your baby, no question - yes you have to be flexible on feed times to keep your supply up to growth spurts, etc, and yes it can be annoying, but going to ff is not a magic sleeping potion, baby's sleep issues are just as likely to be developmental.
Check out the sleep/naps boards - ff babies have just as many problems with short napping and sttn as bf babies do. 5 months is a big age when the short-nap monster hits. EBF is a great thing to do, I wish I could have done it myself (I had to combo feed b/c of supply issues from the time dd was 5 days old). She still had crazy naps at 5 months, and periodically thereafter. She also STTN (10 + hours) regularly from the time she was about 10 weeks old, but then STOPPED at 6.5 months, and didn't STTN regularly again till she was well over 1 year. So obviously the formula didn't make her sleep better.
And FWIW, I was ff from 6 weeks and I have nearly every health problem under the sun that ff raises the risk for, except cancer (knock wood). My brother the same. Sure, we're alive and perfectly functional adults, and I'm really glad we didn't starve (my mom lost her supply due to diabetes) but here's the thing - except for lifelong weight problems, you can't see most of the health issues that ff impacts, unless you know the person and their health history intimately. Just to say, all that scientific evidence is real and it is based on real people, even if they are not always visible.
Hugs! I hope everything works out for you. Fenugreek + blessed thistle was a lifesaver for me in getting/keeping my supply up, especially in growth spurts. And sometimes I had to drink up to 5L of water a day to have enough milk - it's SOOOO important, keep drinking!
Hugs!