After many years I switched from Giganews to Astraweb.
http://www.astraweb.com/
Astraweb is one of the few services that runs their own news servers and has a good completion percentage.
The main reason I switched is because my newsgroup habits have become pretty varied when it comes to how much I download each month. Astraweb offers a payment option where you pay for a set about for a number of GBs and can keep it until you use it.
So, for example. I initially tried out the service buying 180 GB for $25.00. I'm still using it That's the same or less than I paid monthly for the top tier Giganews monthly unlimited service but I probably only download like 60GB a month these days. Whenever you run out of GB's you can just buy more.
Here's the breakdown
25 GB for $10.00 (poor choice)
180 GB for $25.00 (Not bad at all even if you download quite a bit)
1000 GB for $50.00 (great deal)
(there are also traditional monthly fee options but the above works much better unless you really download a ton which most of you can't due to ISP bandwidth limitations)
I'll pick up 1 TB for $50.00 whenever I run out of my 180GB and it should last me qat least 6 months which saves me ass tons of cash ($180.00 Giganews) It may even last a year (unless certain consoles get hacked!) which would be $50.00 vs $360.00+
I get 90+ Mbps on my downloads consistently and 100+ often so there's no issue with download speeds. You can still have lots of connections and retention is 4-5 years. They have US and Euro serverfarms. They take Paypal which is always a plus so you don't have to dish out your CC number to another company if you have a Paypal account which you should...even Best Buy/Newegg, etc take Paypal now.
I really like the pay for GB plan. with 1 TB for $50.00, you won't feel like you're wasting money in a slow download month and you don't lose your allotted GB's ever until you use them.