How do reference speakers rank to today's standard


I think that most of us at this forum had an experience like I am having now: to choose between a once reference speaker and a recent midrange speaker.
For 8 years I have been the owner of Audio Physic Spark III's and I love the sound of the AP's so I want to cling on to this brand. But what to do.
I can choose between two offers, both in the same price range. One is the Audio Physic Avanti II (the year 2K version, the Century), 11 years old and once a reference speaker.
The other one is a 2 1/2 year old Audio Physic Tempo VI.
I know that speakers do age and that 11 years old speakers won't sound as they did 11 years ago.
Also, in the 8 1/2 years that seperate these AP's there has obviously been some development in speaker design.
But do you think that the Tempo's sound better than the Avanti's ?
And what about the (remaining) lifespan of both of them. For the record, I am not able to listen to them at home. Any advice is highly appreciated. regards, Ton
linkingpin
About melting your coil, as in the answer Larryi gave, here is an example you should not try at home. A guy was testing his speakers with a 4hz tone. And was surprised he blew up his woofer :(
Not agreeing with the basic premise here, that speakers don't sound as they did when they were 'newer'.
Our perceptions change, but barring damage or deteriorating surrounds (again damage), they should measure and sound the same.

Good listening,

Larry
I own a pair of Avanti Centuries and a pair of Vandersteen 3A Sigs that are nearly 20 years old. If I had to buy new speakers every 2.5 years I would be listening to Bose or robbing banks.
I got 25 years out of a pair of kef R105/3’s and I was rocking 104-114 db daily. Stepping up from those cost me a fortune. I think inflation has moved much faster than progress wrt loudspeakers. While I’m not familiar with your brand I doubt anything built 10 years ago is missing any new tech,