Given the cost, I think there are better alternatives unless you are considering playing in a lot of FIDE events. However, it is also possible to purchase them used, and then to send them to a Monroi designate to clear the owner information for you.
MonRoi was thoroughly tested by FIDE and they concluded that it doesn’t make cheating more plausible. It is used in a number of tournaments. Scoresheets of any form are to be used move after move. MonRoi was approved in 2005, and if you do a search, you can see that MonRoi is frequently used in FIDE events, with no reports of cheating due to the use of MonRoi.
The Monroi has a scoresheet mode that looks just like a normal paper scoresheet. That allows a player to check on previous moves (for things like a fifty move claim or three-fold repetition) without actually seeing previous positions.