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Surprisingly, installing Ubuntu 13.04 on a MacbookPro10,2, almost everything seemed to work out of the box. But after upgrading to 13.10, there was a one major flaw which is very annoying if not fixed. Wifi connection seemed to be dropping a lot of packets. For me it was at most 50% packet loss. The issue seems to be with Broadcom’s proprietary drivers. Apparently the previous version of Ubuntu shipped with an older version of the driver which seemed to work fine.
The solution is to downgrade the Broadcom driver. I followed instructions posted in this blog post. It covers how to successfully downgrade the driver and make sure no future update is applied to it.
There’s also a bug reported on Launchpad.