We did VPN into our corporate network via the wireless and it is SSSSSLLLLLOOOOOWWWW. We ended up syncing up Outlook each time over a couple of coffees at the Cove Cafe and didn't use the time to actually DO anything with them. The connection dropped quite a lot, also.
I preferred to just use Outlook Web from the internet cafe and not deal with the VPN, but DH liked being able to use his own laptop.
Not a big fan of spending too much time doing work while on vacation, so the dropped and unstable VPN didn't bother me too much, but if you're really relying on it, I think it will get frustrating, unless something has changed.