i haven't heard the sierras, altho i have heard the 340s, which are, i guess one step down their food chain, and my recollection is that they were ok-but-unmemorable. i did audition the eras against psb imagine/synchrony, kef xq and paradigm signatureand thoughtthe eras were significantly the worst--boxy, narrowsoundstage and tinny. now, if you read my posts, you'll see i'm not generally such a naysayer--there's lots of monitors in the same range i really like--psb/paradigm/rega/vonscheweikert/energy et al--but i really think you should look elsewhere.