I'm running a no-magic RMC campaign right now. Technically, it's "very low magic" since such things do exist and the PCs will eventually encounter them. The magic will be my own mash-up of Arcane magic, based on my mythos.
The lack of healing magic gets noticed, just ask the fighters in my group, but the healing arts are more advanced than in a prototypical Medieval setting to make up for that. There are hospitals, and herbs are available.
Now, when I say herbs are available I don't mean the PCs are running around with a pouch full of mirenna berries and such. They have bandages with pre-applied poultices that help to staunch 5+ points of bleeding, provide antibiotics, and accelerate healing. A hurt PC will still be recovering for a while, he just won't be dead.
And such things are not cheap. And I'm not running a GP-oriented campaign. The PCs are spending copper. The PC who is a squire has seen silver money, but he currently doesn't have any (being the equivalent of the starving college student), though he has more copper than the others. So the supplies needed to keep themselves alive will keep the PCs counting their pennies.
There have been a couple of minor grumbles about me not running a "regular" fantasy campaign but it has not detracted from our having fun. They are getting used to the idea. And I'm using the "No-Profession" option; you define your character by what you do.
So far it's been an interesting diversion from the "regular" way. I don't have anything against that, being a fan of magic-using characters myself, I just wanted to try something different and avoid the usual stereotypes.
An important part of this is that I'm keeping things fluid. I just introduced AbtP and the combat system from Combat Companion, some elements of SPAR, and a few other tweaks. (When I introduced armor prices from Chivalry & Sorcery, one guy almost fainted.) Point is, I'm listening close to the players about what's working and what's not, and adjusting how I run things accordingly--within reason. Based on some of their comments I may introduce some magic earlier than I had planned, but it will be a small tweak; suddenly dropping Spell Law on the table just would not fit the game world.
For my own motivation, my choices were inspired by what I've seen as some of the trappings of fantasy being used as substitutes for a good story. Those things--high magic, demons walking the earth--are not needed. Nothing wrong with them, but it's the story behind them that makes the difference.
Two analogies: Star Trek and James Bond. The crew of whichever Enterprise is currently sailing has an entire galaxy to explore, and what do the writers always fall back on? Time travel. I want to puke. It's a complete lack of imagination to not be able to come up with a story in the present.
James Bond (pre Daniel Craig) faces the worst of the worst of humankind, the fancy gadgets and impossible evil plots just obscure the fact that there's no real story underneath. An opponent that diabolical doesn't need a fleet of space shuttles or an island-sized home base, he should be scary enough all by himself. (If you like Bond, you're far better off reading the books.)
To be fair, if those stories actually had a story I probably would not be complaining about the other stuff. Either way, it's the story. So, let's have a fantasy campaign with some story. Now, I've set myself up for a serious workload. I'm having to work harder than if we were doing dungeon crawls. But, I think it will work out well.
This post wound up a lot longer than I intended. I hope some of it helps. Does being a blowhole make me a better GM, or worse?