MC cart rebuild frequency: a question for you

I heard an interesting -albeit a little discouraging- point of view regarding fancy MC carts installed in highly revealing systems. I am not sure what to make of it all.

The gentleman in question listens to several hours of music on vinyl records seven days a week. He says he notices his cartridges sounding tired after a few months, and that cartridges should be rebuilt/replaced every year or so irrespective of use, and after they have been cued a few thousand times the fragile assemblies need replacing or rebuild. They still work, but the difference in the sound is noticeable once you put a fresh new cart in. Notwithstanding "break-in" sound, of course.

I like to think my system is revealing and my VDH cart -purchased new- is an expensive item in my world. It still sounds good to me after two years and I am I not noticing it getting "tired" because the decline -if any!- is so progressive, kind of like getting fat with age: if we gained 20lb overnight we would freak out, but since it is gradual we hardly notice...
...until we install a new identical cart.

In other words, would one be better off having two identical $1000 carts on a rotation (one in use, the other in the process of getting rebuilt) of one rebuild per cart per year to keep all moving parts "fresh" and carts always in peak condition, or would one be better off with a $5000 cartridge getting a rebuild every 5 or 6 years, or 2000 hours, whichever comes first.

See what I mean? Is the sound of a lesser -but fresh- cart better than the greater cartridge on a less frequent rebuild/replace schedule, all other things being equal, using only freshness and newness of the suspensions, cantilever, diamond, as a criteria.

I do not have the financial means to conduct the experiment for myself. I figure since the market for used cartridge is alive and well, the difference between a "aged" low-hours cart and a fresh one have to be minimal, otherwise no one would buy them and it would be well-known.

I'd like to hear what you think, what your experiences are.
I agree, the wear on carts happens very gradually. I didn't realize how much wear had occurred on my Dynavector XX2MKII, until I was having problems tracking RR's Doug McLeod's "There's A Time". I even called Reference Recordings to ask them about the noise I was hearing.

I got to thinking about it, and realized how many years I had been using the Dyna (about 8!), and that it was time for a retip.

I sent it to Soundsmith for their best retip. When I got it back, I was stunned at what a good cartridge it is, and even more so when it turned out sounding better (much better, in fact) than it did when it was new.

I don't know at which time performance actually starts diminishing, but I do believe one year is, in most cases, not necessary. Of course, we all do things a bit differently, and have various abilities in cartridge set up, and how we use, or care for, our records, carts, etc.

It's good to have more than one cartridge that can be used as a comparison to judge a cartridge against, especially if the spare has low hours on it. It would probably help if the carts are similar sounding, to make a comparison more valid.

This subject is one I have thought about, ever since getting back into vinyl about eight years ago. Still learning, and that helps keep my interest up.

I have and use more than a dozen cartridges. I have sold used cartridges. Without fail, my buyers have been very happy with their purchases, probably because they were upgrading, even if used. So, those used exotics sound better than their new lesser cartridges. I do not hear a drop off in quality so long as there is no physical damage to the stylus or the suspension has collapsed completely.
I spoke to the Benz Micro people when I bought my Gullwing SLR, they estimated that I would get about 1500 hrs, maybe more if my records were clean and the cart was well maintained before a decline and need of a retip. I then started tracking hours of LP play time, actually less than I expected. After 18 months I average about 275 hrs of LP listening a year. So about 5-6 years is a good estimate. I then sent my Shelter 501 II that I had used for 19 months previously for similar use, to two separate Vinyl experts to look for wear. I was surprised that they both estimated that I had about 35% wear or 30-40%, ( one was more precise ). they both compared to new Shelters. Which is about right for about 500 hrs of use. So, unless I hear my cart making funny noises, it gets sent to the Cartridge extreme makeover guy at 5 years, the shelter goes in and when the Benz comes back, it takes over for another 5 years.
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To extend this discussion slightly, does anyone believe there are differences in wear rates between makers. I have seen it said that Koetsu, for example, are the Mack diesel trucks of the cartridge world and will last 3000 hours. Certainly, I used a Rosewood Signature I bought here on the Gon and used it quite heavily for 3 years, with no easily detectable change.

The trouble with retips is, by the time it is returned, you can't really recall how it sounded before.

I am a big enthusiast for retipping. I have had several cartridges done by Expert Stylus here in the UK, with uniformly excellent results