I believe a lot of the guys on here use Yesbets, and vouch for it. Personally I use Oddsmonkey and think its the dog's danglies.
Read through some of the earlier posts and users shows screenshots and their views on each sub.
I'm an Oddsmonkey devotee , their range of tools to use is exceptional. I actually split the monthly cost with a mate from work and we both use it. So for £7.50pm its cracking value. Since the start of Euros I'm over £300 up from the reloads alone ( gubbed from PP so missing all those lovely offers from them)