The use of any machine, or device, which involves lifting, pulling, pushing, will affect spinal stability, as stability the spine / pelvis is dependent on Balance, that is, muscles in balance.
All physical work, which entails extended use of specific muscle groups requires a balancing action, otherwise body balance / alignment is comromised.
Bear in mind, I'm NOT suggesting that any particular system is the equal to, or superior to another, just saying that different people will achieve hugely differing results from the same machines and some people will get perfectly acceptable, in some cares exceptional results, from, lighter, less expensive, easier to use devices.
As most L/M systems tend to glide, with little effort, the will be less demanding than the downward force of hoses.
In terms of how little this affects the individual, it's a lottery.