I love my iPod. My wife loves her iPod. We had "issues" when we realized we had two iPods and only one iTrip. So when I heard about Macally's BTCup, I figured it was going to be a problem solver — wife gets the iTrip, I get the BTCup.
The first problem cropped up when I "installed" the BTCup. I put the quotes there because you can't really call it an installation — you stick it in your cup holder and you're done. The problem was that my cup holders are too big; they have a raised frame designed to hold wider cups, and the BTCup is too small. New plan — I keep my iTrip, and my wife gets the BTCup for the van.
The sound quality on the BTCup beats my iTrip. It's got a richer, fuller sound — even though it transmits the exact same way as the iTrip. We don't have to turn the sound up nearly as high with the BTCup. Score one for Macally.
The beauty of the BTCup is the BT — Bluetooth. There's an integrated Bluetooth microphone on the base of the BTCup, so you can answer the phone in the car. That in and of itself would be valuable, but the BTCup transmits the audio to the car speakers. You can hear the person you're talking to in stereo sound! Of course, there is also a small, wired headset to use if you don't want your entire carpool listening to you talk to your spouse on the way home from work. And the BTCup automatically mutes your iPod (though I wish it would pause playback) while you're talking. That's two for Macally.
The only real drawback that we've found has a lot to do with the location of our cup holders. The cup holders in the van are between the two front seats on a console that only comes up as high as the seat bottom. This creates two problems: first, it's hard to see the iPod screen and use the controls to change tracks, etc. Second, the Bluetooth microphone doesn't pick up so well from that distance. This isn't really a fault with the BTCup, because I'm sure it would work fine in a different setup. Just a word of advice — consider where your cup holders are before investing in a BTCup.