Hey ge,
I've had most of the VMPS speakers of the latest generation including 2 pairs of 40s and a pair of 30s. The 30s had the auricaps, silver wire, megawoofers, SR-71, and I did the 10" passive woofer replacement while blocking the 2 holes underneath--much better bass. Both the 40s had most of the upgrades including TRT caps, silver wire, FST tweeters, SR-71, with the latest one also having the MLS cabinets. The 40s have a bigger sound, more effortless, will play louder, taller soundstage, and have a fuller balance (though this is a lesser issue after doing the 10" passive mod). The 30s might have a hair more definition. The 40s bass is like a sledgehammer with clarity. If size does not matter, it is worth the trade up to the 40s. If you don't have the bullet-nosed phase caps on your 30s, it will be a very big difference in bass between the 2 speakers. All of the VMPS speakers that have the neopanel mids are very nice sounding speakers and their adjustability to different rooms and systems is an awesome feature in my book.
Hope that helps,
Bob
