I do wonder why there isn't a DI out on the Amplifi. You can get all the tones you dreamt of but who wants to go back to using a mic to get sound into the FoH? I guess you could use the floor version but then you're relying on a really good monitor mix.
Was it designed just for bedroom use as a local dealer told me recently. He described it as a toy for students in bedsits!! Guess he had a downer on Line 6 anyway as he also said that the Variax wasn't reliable. I've been using them since they first arrived and they've been great. You just have to do a little tweaking, but I've had Gibsons and Fenders and they needed tweaking as well.
You can always mic the 150 if you want to. It sounds fine that way.
As far as your dealer, I've never understood why someone would badmouth a product line they sell. I've always thought that having a product to sell in your store is something of an endorsement of that product. As far the Amplifi being a "toy for students in bedsits", I'd say that Line 6 has been pretty forthright in advertising the Amplifi line as a more practice-oriented product for home or home studio. But it doesn't mean it couldn't be used live.
All this talk of "bedroom players" reminds me of a poll I saw over at The Gear Page site. It's an internet poll, so it's not scientific or anything, but of the people who responded to a question about how many of them have ever played a gig, 75-80% of the people who responded had never played one gig in their life. So I guess what I'm getting at is that regardless of what the actual percentage is, there is a large contingency of players out there who do most or all of their playing at home, and if you're a company that makes guitar gear, it makes sense to make some products that are aimed at that demographic.
"It is not our duty to understand the arbitrary, meaningless dictates of machines"
- Don Norman in The Design of Everyday Things