I'll second Art's comments. The key to having a great bike is having a
great fitting bike. A poorly fit $5000 bike isn't all that great and
you'll get much more enjoyment out of a well fit $1000 model.
Sure if your fit is dialed in and you or your friends are experienced
with fit and mechanics a mail order bike can save you money and be fit
just fine. But that dopesn't sound like your situation.
My understanding is that the margins on bikes (as opposed to
accessories) is rather thin. So it is unlikely that savings are goin to
be huge.
I'm riding a 10 year old Litespeed and love it. Mainly because I had it
fit properly when I bought it. So, if it cost an extra $100, that's
about $10 a year for a great bike fit.