I have a private proxy subscription, but lately they've been returning a lot of time out errors. Are there any recommendations which company to use for proxies?
I used to have plenty of success with https://buyproxies.org and their shared proxies. Looks like they are calling them semi-dedicated now. I'd get about 15 of them and set to a 60 second delay and never have an issue.
If you're scraping Google, grab 10 - 15 dedicated proxies (search around, you can get for as low as $1 each).
Use the single threaded scraper and SB will rotate through your private proxies after each search query is complete. That way you avoid bans whilst not breaking bank having to buy 100 proxies.
Also for Google scraping, shared /public proxies will not get you very far!
I use the guys from Storm Proxies. The proxies are constantly rotating with each http request making them better than private/dedis which will eventually just get flagged and banned.