I just answered a similar question in another thread, I thought the same answer might apply here... so here goes.
I'm convinced most folks load their muzzleloader much tighter than they did 150 years ago and may need a range rod to hammer down an uber tight prb.
I used my ramrod and only my ramrod for years, and replaced it several times, using (gasp), dow rods from the discount center.
I have several range rods, and I use them... at the range. In the field I usually use the ramrod the gun came with, or the one I made for it. BTW, now I don't use dow rods...often. I never had one shatter, but had them crack and fracture while using.
That being said, if I'm in a dove field and shooting a lot while standing pretty stationary i'll carry a range rod, it is admittedly easier to load with than a ramrod. Otherwise, I will use my ramrod.