This is what dealers are for; good ones have burned-in examples of the things that they sell.
Lacking that, perhaps you live in West Texas, then it is correct to assume that components will only get better with burn-in; however, some really outstanding components can sound ugly on first hearing.
You're auditioning a couple of good brands, so you'll likely be ok. Particularly listen to music with lots of low bass. Can the amps control your woofers? Some will not and can be eliminated. As for the mids and highs, it's a crap shoot until the amps burn-in, IMHO.
Dave
Lacking that, perhaps you live in West Texas, then it is correct to assume that components will only get better with burn-in; however, some really outstanding components can sound ugly on first hearing.
You're auditioning a couple of good brands, so you'll likely be ok. Particularly listen to music with lots of low bass. Can the amps control your woofers? Some will not and can be eliminated. As for the mids and highs, it's a crap shoot until the amps burn-in, IMHO.
Dave