I have an electrum wallet and do trades with my some of my bitcoins there but the thing on electrum. I only trust it's security but with it's fee it's higher than blockchain.info. If you want to have some lower fees, you can go with blockchain.info this is the web wallet that I've known so far that is even more charging lower fees. You can also set the fee on your transaction if you want to pay lower fee but expect that it will take a lot of time so make sure that you don't need it on a rush.