I have the Bosch 1617 router and thought I could get away without a lift. It was such a pain in the butt. You always had to reach down, unlock the latch, move the router, check, remember to lock the latch (which I rarely remembered to do), deal with drift because the latch wasn't locked etc.
I got the Incra lift. Not only is it easier to use because you do everything from the top (including lock/unlock of the lift mechanism), I believe I can make finer adjustments (or at least I can see how much I'm moving since there's a dial that shows how much adjustment I'm making. Also, I have more range of adjustment than I had with the Bosch mounting.
It could be my imagination, but it's lots faster and easier to get the router to adjust exactly to where I need it. This means that I have less emotional resistance to using my router table and can get more done. That alone was worth the price and time to install. I'm now considering the device that will measure how high/low you're moving the router to avoid multiple measurements. But that may be a "want to have" vs a "need to have".