Vodafone NZ HSDPA Broadband XU870 on MAC OS X

I use Vodafone NZ Mobile Broadband (HSDPA) service with a Novatel Merlin XU870 ExpressCard, with my MacBook Pro OS X 15.3. For majority of times, the connection has been somewhat unstable.

When I first move to OS X 15 Leopard, Vodafone NZ does not support it the new OS X operating system. I have to resort to reading tones of forums and trial and error to figure out a way to make it work. I did manage to get it working just using Leopard's build in software and driver for the XU870.
Go to system preference -> network -> select XU870 -> Advance Option -> WWAN tab -> Select Novatel in Vendor drop down list, then click apply (important otherwise next option will not appear), then select GSM in model drop down list, then enter www.vodafone.net.nz into APN textbox , leave CID as default (1). Click Apply.
Back to general setting page and click on connect, you should be able to connect. After this, you will be able to see signal strength and connect and discount from task bar icon.

The above work around approach works, but it is not very stable (at least for me), the connect sometimes just hang, you can send requests (upload traffic) to server but does not seem to be any reply (download traffic), you will need to discount and remove the XU870 card and reinsert it then reconnect to make it work again. This is rather annoying. Not entirely sure if this problem is due to hacked way of set it up or it is simply because of Vodafone NZ's crappy service. One way to keep it working (connected) is to open something constantly using the internet connection; e.g. remote desktop, radio player.

Then May 2008 Vodafone NZ finally supported OS X 15 with new software Version: 2.08.05.04; 6 month after launch of Leopard .(Link to download vodafone software) I thought it might be better to use the Mobile Connect software, and it might solve the unstable connection problem. However, I am hoping too much, it is not the case. it make things worse than before, it is still unstable as before, (maybe a little better but not much), the connection still hang every so often. And it is more difficult to connect and disconnet, to do these you will need to go to the system preference network page.

Then today I come across this Launch2Net software. It suppose to be really good by reading the reviews, such as this one. But it cost 75 euros just for a single license. Very expensive, is it too much to spend just for more convenience? Have to think again