I've got an 8330 on virgin (owned by bell and on same network)
A stock 5.0 build isn't available via either carrier and the stock 5.0 builds by other carriers are riddled with flaws.
However I am running 5.0 although it is a hybrid and it works pretty awesome. Go to
www.bbtweaks.net or
bbtweaks.com | I'm not sure which it is, they have the hybrid there. They also have a pretty built proof walk through on how to upgrade.
Keep in mind that after you upgrade you'll need to replace all apps and themes and you will almost always have to download apps and themes for the 8530 running 5.0 and not for the 8330(as 5.0 really isn't supported for 8330's). Sometimes you can run into a few problems with memory leaks as the 8530 themes and apps sometimes hog more resources, which means you may have to do a few more battery pulls then usual to reset your device memory.
(once a day works good for me, usually in the morning. I'm also bbm heavy which seems to draw more device memory then anything. In this case clearing group chats often helps dramatically.)
This however hasn't been a huge problem for me as a full restart usually takes 5 minutes or less unlike the 15-20 minute reboots I had with 4.5
Its a pretty basic procedure, but takes roughly an hour to do.
If you'd like more info feel free to bbm me, here's my pin:31F8F344
Hope I was informative
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