There certainly are very good analog systems out there. I haven't used the Carvin one, but I used a Sennheiser for the last 7 or 8 years before moving to the G90. It sounded very good, but in the end, an analog system with a compander is going to lose something. Now, I'll grant that going digital doesn't automatically mean better -- poor A/D converters, slow converters that add delay, or other issues could be introduced to match or exceed the problems of a compander. But the Line 6 gear, from what I've observed both in my own use and from what I've heard others say, doesn't have any of those problems. It's a well implemented digital system. You need a very, very good compander to overcome the inherent problems a compander introduces, and even then I'm not sure you can ever really match a system that doesn't need one. You're taking something away (dynamic range) and then trying to add it back in after the fact. It's tough to do that kind of compression in an analog world without losing something.
Do plenty of pros still use analog systems? Absolutely. Can you really tell the difference in a loud, full band setting? Maybe not. But is a well implemented digital system going to sound better, observed objectively in isolation? Almost certainly. At the price of the Line 6 systems, I don't see why you wouldn't want to have that little bit extra.
