I have no idea how it is supposed to work, so just dumping the data from here (leading to bad experience).

Running (from UK) urpmi.addmedia --debug --distrib --mirrorlist '$MIRRORLIST'

It starts using mirror http://mirrors.yun-idc.com/, in China.

parsing: /etc/urpmi/mediacfg.d/Devel-4-x86_64
cached mirror list uses an old format, invalidating it
URPMI_ADDMEDIA_REASON reason=upgrade
getting mirror list from http://mirrors.mageia.org/api/mageia.4.x86_64.list?reason=upgrade
retrieving   mageia.4.x86_64.list?reason=upgrade
'/usr/bin/curl' '-q' '-s' '--location-trusted' '-R' '-f' '--disable-epsv' '--connect-timeout' '60' '--anyauth' '--stderr' '-' '-O' 'http://mirrors.mageia.org/api/mageia.4.x86_64.list?reason=upgrade'
retrieved   mageia.4.x86_64.list?reason=upgrade
using mirror http://mirrors.yun-idc.com/mageia/distrib/cauldron/x86_64

After a few downloads, /root/.aria2-adaptive-stats contains:

host=mageia.c3sl.ufpr.br, protocol=http, dl_speed=936692,
sc_avg_speed=936692, mc_avg_speed=0, last_updated=1381673413,
counter=1, status=OK
host=mageia.mirror.dkm.cz, protocol=http, dl_speed=0, sc_avg_speed=0,
mc_avg_speed=0, last_updated=1381673400, counter=0, status=ERROR
host=mirrors.yun-idc.com, protocol=http, dl_speed=0, sc_avg_speed=0,
mc_avg_speed=0, last_updated=1381673397, counter=0, status=ERROR

/var/cache/.metalink file, it definitely doesn't look right:

<?xml version="1.0" encoding="utf-8"?>
<metalink version="3.0" generator="URPMI" xmlns="http://www.metalinker.org/">
<files>
<file name="descriptions"><resources>
<url type="http" preference="99"
location="cn">http://mirrors.yun-idc.com/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="ftp" preference="98"
location="za">ftp://ftp.sun.ac.za/pub/mirrors/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="http" preference="97"
location="cz">http://mageia.mirror.dkm.cz/pub/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="ftp" preference="96"
location="de">ftp://mirror2.tuxinator.org/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="ftp" preference="95"
location="de">ftp://ftp5.gwdg.de/pub/linux/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="http" preference="94"
location="br">http://mageia.c3sl.ufpr.br/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="ftp" preference="93"
location="nl">ftp://ftp.snt.utwente.nl/pub/os/linux/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
<url type="ftp" preference="92"
location="us">ftp://mirror.nexcess.net/mageia/distrib/cauldron/x86_64/media/core/updates/media_info/descriptions</url>
</resources></file>
</files>
</metalink>

So it lists mirrors from South Africa, China, Brazil, ... but not the fast one from UK.

Looking at /var/cache/urpmi/mirrors.cache, it is in the list:

                                         {
                                           'version' => '4',
                                           'continent' => 'EU',
                                           'zone' => 'GB',
                                           'city' => 'Canterbury',
                                           'latitude' => '51.2987',
                                           'url' => 'rsync://www.mirrorservice.org/mageia.org/pub/mageia/distrib/cauldron/x86_64',
                                           'arch' => 'x86_64',
                                           'type' => 'distrib',
                                           'longitude' => '1.07005',
                                           'country' => 'GB'
                                         },


But the chosen one is in China:

'chosen' => 'http://mirrors.yun-idc.com/mageia/distrib/cauldron/x86_64',


Reproducible: 

Steps to Reproduce: