The Apogee stuff is, IMO, terrific. One of the singers I work with uses their MiC and iPad for voice-over auditions. Here are a couple of things I did with the Jam and Garage Band on my iPad:
Me attempting to program built-in drums, but otherwise all Roscoe - fretted for chords & bass line, fretless for melody/solo.
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Drum loop, canned organ voicings, Roscoe fretless. (Weaksauce warning.)
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It's really all about defining expectations. You're working at home, trying to memorialize ideas, and perhaps measure and track your performance progress. To that end, it's hard to go wrong with any of these products in the < $200 range. FWIW....I've done pre-pro/demo work for a few album projects, and those gigs pretty much covered the cost of my entire setup (Presonus AudioBox USB & Studio One software, with a set of M-Audio powered monitors). To that end, I find the Garage Band thing a bit too tedious, but if you're just out to learn and have fun, spending the few $ on the iPad app and $100 on the Apogee Jam will net you great results.
This one has been shared before as well, but here's something I put together in Studio One, using my GrooveTubes DITTO into the AudioBox USB interface. Canned drums, all else is fretted Roscoe sixer.
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Regarding the back end, I'm very surprised there hasn't been more USB 3.0 hardware on the market. That, and of course Thunderbolt, has pretty much put Firewire to bed.