In general, soft contact lenses are a lot more comfortable than rigid gas permeable (RGP) contact lenses. They are also much easier to fit, and can give very good vision.
Both soft and RGP lenses may be suitable for many people. But each has their potential pros and cons.
For example, soft contact lenses maybe a little more drying to the eye than RGPs, and for people with very high spectacle powers, sometimes soft contact lenses may not allow such a long period of wear each day because of issues with oxygen transmission with thick lenses. Toric soft lenses can sometimes rotate with each blink and give fluctuating vision.
RGP lenses overcome many of these issues. They are less drying, and even with high spectacle powers can allow whole day wear because of excellent oxygen transmission. For low degrees of astigmatism, plain spherical RGPs can be used, so that there is no fluctuation of vision with blinking. RGPs are reputed to give the clearest possible vision of any correction method.
However, RGP lenses typically take several weeks of daily wear every day to get used to, and if any dust or foreign body gets in the eye, the pain can get quite bad until the lens is removed and washed out.
Monovision is a different topic altogether. Monovision can be achieved with any kind of contact lens, spectacle, cataract surgery, or refractive surgery (eg LASIK, PRK, SMILE, ICL etc).
Monovision means using one eye to see far and the other eye to see near, and is used in people with presbyopia ie above the age of 40 and having trouble reading when they wear their distance glasses/contact lenses.
Monovision has no effect on eye health over and above whatever is being used to achieve it eg contact lenses.
Monovision is a compromise, and when you are not used to it, the feeling is that things are not as sharp as they used to be. So people with monovision from contact lenses or surgery sometimes may still wear glasses eg to drive at night, or to read really fine print. The beauty of contact lenses and monovision is that if you don't like the feeling, you can just switch back to your original distance correction contact lenses.
