As already told, theres no "best".
What you can do is do compare some pools on following facts:
- Uptime
- DDOS-Protection
- Do they run custom software?
- Payout System (PPLNS,Prop...)
- Did they already payout?
- Support Speed
- How many Blocks they found
- User experience (Google for it)
- Financial Stability
- How long are they online?
- Do they successfull run any other coins?
- Security (Two factor auth)
And so on
, good luck with choosing your Pool !
+1
Plus check the two biggest pools then see the number of shares you get in a give period of time lets say 12 hours
then see how many blocks per day were solved in one pool and check the other as well
Difference is small specially if a pools has fees when the other does not, still the difference is a round of shares at best.
Now Guild has email notification when a worker is donw when Ghash has for the total hashing (not so helpfull in my opinion)
Anyway as I said small difference.