It states in the manual that tank life will be shortened. The long term stress of any surge type device weakens the seams. Realistically a well built glass tank lasts 20 years, the wavebox may shorten that to 17 or so. I have an 8 year old 180 and as soon as I get the chance I am replacing it due to scratches and silicon discoloration and trim fading so in reality very few people keep a tank long enough to encounter this issue, they replace it long before for other cosmetic reasons. Tank life also varies substantially, big tanks move very poorly, being drained , moved and filled substantially shortens the life. If the stand is unlevel this will also have a big effect so there is no way to know for sure how long a tank will last but I don't think in most cases the wavebox will be a big issue.
