master_rb - Why not register w/ DSLr? - There are a number of benefits, it is free AND your privacy will be respected as much as you desire.
In reguards to speeds that you should expect, the max is described above.
Additionally, there are some fine points (at least IMHO).
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---(1)--
Max speed still is attained ONLY when all connections along the way ("hops", "routers", etc, etc and whatever) are working near perfectly
The speed tests available here (and elsewhere) will quickly demonstrate how one "route" (sometimes to the same destination) can be quicker than another (and this will vary also by time-of-day). This is true regardless of the
connection type (analog, xDSL, ISDN, FIBER, Wireless, etc, etc )
--(2)--
Many ISDN charges are based on the various things depending on the telco AND the ISP.
In my case, I have unlimited time charges on each "phone line"; however, after 100 hrs per month my ISP charges $1.00 per hour.- No big deal, . BUT the ISP charges the $1.00 per hour for 128K connection. The ISP is good about the time @128K - seldom more than 20-90minutes per month.
Since some telco's and/or ISP's charge much more and on a time basis, the "modem-and-software" can be configured to limit the connection to 64K when 128k would not be advantagous (normal e-mail and congested internet ).
Back to your original question: When I use my Netscape notation to measure my speed (eg, downloading one of the "WHO" pages), the speed starts at about 3.3K/secs and increases. When it reaches about 7 or 8, I can see by the tell-tales on the "modem" that it switches to both channels. It then climbs to a max of 16 - 18 K/sec.
I have seen at other times 22K/sec on kinds of download. While this might result from the "compression", I don't particularly trust those values.
On the controled speed tests here at DSLr, I generally get 119 - 122 K rates.
The difference of seeing 16-18 versus 119-122 measured, will be left for another discussion elsewhere.
(I gotta go to work

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