Hello everyone

Hoping to get some input from the community here regarding my current situation. A little bit of background first. About a year ago, I ported my number (area code 905) to voip.ms. The number was our home number and I was just sick of paying around $30 per month for a number we rarely used. However, I didn't want to get rid of the number as many companies (bank, hydro, gas) all had that number on record, so I decided to port it. Initially I had setup the number to forward to my cell phone, however, as it was a business number, that became quickly impractical. I then changed it to simply go straight to voicemail instead, and anyone that called (excluding telemarketers) could leave a voicemail. I wasn't a big fan of this idea however, as I would have rathered just answered the call and dealt with whatever needed to be dealt with.

Long story short, I decided instead to use the SIP client on my Samsung Note 2 to connect to the voip.ms servers. The service however, wasn't as "great" as it seems everyone else is experiencing. On virtually each call, the other party indicated that their was either "static", an "echo" or most commonly a fairly significant delay in hearing my responses (about 3-4 seconds which makes a conversation difficult).

At first, I thought it was simply the voip.ms service, however, almost all of the reviews I have read say it is GREAT. So before I do anything like switch providers, I wanted to ask for some input from other VoIP experts here.

Is there something I might have configured improperly?
Do you know of any issues with a cell phone SIP client?
My cell will usually connect to the wireless network of the location I'm at (work and home), could this be the issue??
About 25% of the time, my phone won't even ring, the call will just go to voicemail. Is this normal???

I'm hard pressed to believe that VoIP service is this "shoddy". I have to think I've got something mis-configured.

Thanks a lot for everyone's input!!