Advised for speed and reliability
SQUID proxies offer a great price and a good service. I actually use SQUID proxies myself and have been a happy customer for years now.
SQUID have the best prices for buying bulk proxies and the extra 20% could make SQUID Proxies the best deal, check it out to find out.
Proxy hub provide UK and US proxies which, being in the UK, is great. Proxies were quick and worked right away without issues.
Proxy-Hub have been providing proxies for many years now and are very active on a lot of SEO and Proxy forums and have gotten a reputation for great service. Coupon above is good for 10% off recurring
Another private proxy provider that is reknowned for reliability. Proxies have good speed and are distributed just across the US or Europe so if you need proxies specifically from either of these areas then this is your provider.
The My Private Proxy site has a lot of useful uptime information for their proxies as well as a full rundown of specs for the machines that the proxies are on so you know what you are getting before purchasing.
Good reliable proxies
Buy Proxies is another proxy provider that I have used for a long time, I do not currently use them purely because I have been happy with SQUID proxies but I can attest for the high level of service with Buy Proxies.
Buy Proxies have great support. If you ever have any issues with any of their proxies I am sure you will get help with it in a short time.
I haven't personally used SSL Private Proxy but have heard decent things of them and the 15% off discount code certainly helps
They may not be as well known as a provider like SQUID proxies but they do have some helpful monitoring information in the members area so you can check if your proxies are working without having to run them through a proxy checker