If you need an escrow for service i can recommend you to a very reputable escrow he already handled 20-50 btc transaction by escrowing it.  Pm me here in forum if you need escrow for better and smooth transaction. Buying 20-30 btc is quite dangerous for sure if you don't require escrow.
For clarification, i am not going to be the escrow i am just going to recommend some reputable and trusted escrow with high ranks that i know here in forum.