I bought an Amplifi 75 the day they came out in GC. It's the only piece of gear I use EVERY day. It fits nicely on my desk, and is awesome for practice. I also play out with it every week; it's super light, and it sounds absolutely great. As with any Line 6 piece, the difference between what you hear in the headphones is pretty different from what comes out of the speaker when it's cranked up, so you need to make sure that you can tweak your sound once you're on stage.
The iPad holder on the top is a great touch. The only 2 issues I have are fairly minor, and not really the amp's fault.
1.) When your phone or iPad is in remote mode, the battery drain is pretty ridiculous. I charge my iPad before a gig, and from soundcheck to shutdown, the battery will drain as much as 70%. It's as if the bluetooth is constantly chatting with the iOS device... I'm sure they'll address this in a future FW update.
2.) You absolutely have to remember to put your phone or iPad on Do not Disturb. If the bluetooth is linked, all of your text message and email sounds play right through the amp.... and pray you don't get a phone call while you're on stage! I don't know if it would be possible, but a "gig button" on the remote would be an awesome feature. It would put the device into DnD mode, and avoid inadvertent interruptions. Thankfully, it was just during soundcheck that I learned this lesson!
Other than that, this amp is awesome. It sounds great at home, it's loud enough for a small club, and for bigger venues, mic it, and enjoy!