Would you buy this mohair sofa?  

in a word, no. It's horrible...
in a word, no. It's horrible (IMHO) and not worth $375 of anyones money
;o)

To each his own, but...
I'd have to say no--or, if I'm being frank, "NO!!!!"
I think this sofa points to a time and style that's ornate and superfluous, whereas the other two pieces you mention are honed down to essential functional balance and beauty. This looks to me like Botticelli's clamshell, the one Venus rides around in. So, um, no. Please. In the name of all that's clean and simple and fine I say 'no'.
But if you like it, hey, who am I to judge. : )

errrr
wtf?

lmfao @ Brent
lmfao @ Brent

just imagine how many kids...
just imagine how many kids have been conceived on that thing. I bet they are all in their 70's now. ;o)

OK.... about the children being conceived...
You got me with that reply. 🙂 That's why I need you guys! I love this forum. It's a screaming NO then 🙂

lol ;o) we are here to help...
lol ;o) we are here to help after all!

Warning: Sarcasm Content
Oh, but it's SO pretty and I looooove the color...so sophisticated.

Bordello
If you're opening a bordello, however, it would be perfect. You might also get heavy purple vases with thick, suffocatingly sweet flowers stuffed in them. A black shag rug. An Elvis portrait in great baroque gold frame behind it. It's looking better all the time.

To Brent
Love your suggestions Brent! Elvis, gold frames and black shag rug... perfect! 🙂

looks aside....
....it's probably hideously uncomfortable give the age of the padding and springs.

The ugliness factor of...
The ugliness factor of furniture is more often than not, directly proportionate to its comfort factor. Suck it up, you minimalists! That said, there's more to life than comfort.
You can throw bottles at me, if you want, but I can actually see this sofa looking pretty nifty in the right interior, and reupholstered in a dark blue mohair velvet. You'll need Barbara Stanwyck to really pull it off, though.

DUSTY ROSE
Oddly,I like it in a strange way...mohair lasts FOREVER...

OH,
the frisson of an eames surfboard table in front of it....