I am raising bars due to age and arthritis but this 145mm stem rise with a aluminum steerer tube adds a lot of loading and would make me very nervous over time. While a steel or titanium tube can take an infinite number of loads under their fatigue limit aluminum can not, it does not have a limit at which it starts fatiguing, every even small loading can eventually add up to a failure. Fortunately aluminum frame designers know this and build frame with this in mind.