I have ADSL from SNET... which became SBCGlobal... which became AT&T.
I'm generally happy with it since outages are few and far between, and what throttling they may or may not do is pretty subtle.
ADSL Runs about $20/mo for standard speeds. Higher "business" speeds are available for a higher monthly rate. Cable is about $40, and a T1 goes between $300-$500 depending on where you are; who you get it from; and what additional features (managed router, boundary security, VoIP, etc) come bundled with the package. Sprint's T1 has traditionally been the cheapest offering for us when it's locally available.
Rather than use artificial tests I use the download time for a CD ISO as a rough 'utility' for testing line speeds. Most ADSL connections in my area need about 1 hour and twenty minutes to grab a 650mb CD image. Optimum Online cable does it in about 15-20 minutes. And a client T1 in a lightly trafficked office can do it in about
65.
None of these are scientific tests, but I think they're fair representations of what people in my area can reasonably expect performance-wise in 'real world' terms.
As you can see the performance isn't stellar. But it's not bad for most purposes.
I'll give it a 3 out of 5 rating for my area.

Addenda:
Just for completeness, here's my speed per speedtest.net

And the related quality test from the cousin ping.net site:

Note: I generally prefer using the
MySpeed tests available
here.
They're more detailed and possibly more accurate. At least according to the techs from the various ISPs and VoIP providers I've asked. At any rate, this is what they all seem to use when they're on a client site. See results for my home connection below:

According to this, a 650Mb ISO file should take approximately 71.5 minutes on this connection - which is pretty close to my previously mentioned ballpark average of 80 minutes for most people on a similar connection in my area.
