If $100 means so much to you that you'll hold off for months to buy this lens, then this lens most emphatically isn't for you.
The 50 f/1.4 is a superlative lens that even generally outperforms the L. For double your money you get an extra fraction of a stop and "superior build quality." Big whoop. It has got to be the worst bang-for-the-buck in the Canon lineup.
If you really need that extra fraction of a stop, then you're making enough money off your photography that you're not sweating over $100. If it's build quality that you're interested in, put the extra $800 into a bank account. After several years of heavy use when the f/1.4 finally breaks, toss it and use the money you set aside to buy a second one. You'll still come out ahead.
In short, this lens is for people for whom $1500 is chump change. If your reaction at discovering that your car needed $1500 of repairs would be anything beyond mild annoyance, don't buy this lens.
(If you do have that kind of money, sure, go for it. Why not?)
Cheers,
b&