I have the 2011 (?) zamak model, which was reserved for serious beard accumulation removal; a ceremony akin to a coronation or christening, requiring special preparations, and one which I rarely perform.
Earlier this year I bought the stainless version, which is a weightier and longer thing, and by rights should be more challenging. I was therefore pleasantly surprised to find that it gives me the same quick removal, but more smoothly and easily.
It's not clear why this should be, but the comb seems slightly different. Perhaps the extra heft means that I instinctively use less pressure, and avoid the innate tendency to handle it as I would my usual razors.
Any R41 is, for me, far less dangerous than the Merkur Futur, but I wouldn't normally use the R41 for daily use, as it does need extra care and attention, and I have other razors for day-to-day shaving. When I do fetch it out on rare occasions, I usually put an Astra blade in it, and I think that it needs a "medium" blade i.e. neither blunt nor too sharp, to be reasonably easy to use yet still shave with one pass, or possibly two at the most.