Focusrite 2i4 or Presonus 22vsl or Presonus iTwo?

I think the first two would be a toss-up - they are pretty evenly matched.  I happen to own the bigger brother Presonus AudioBox 1818VSL and it has been rock-solid for me, but many many folks in the Sonar forums have posted about how happy they are with their Focusrite audio interfaces, as well.
 
The 3rd one you list up there - the Presonus iTwo - is almost $50 cheaper than the other two, but may have a set of lower quality mic pre-amps than the other 2 listed.
 
Others will likely post some thoughts on their experiences with these interfaces too, so hopefully you will get some good ideas on which one to go with. :)
 
Bob Bone
 

There are cheap audio/interfaces, medium priced audio/interfaces, and expensive audio/interfaces.
In the end you mainly get what you paid for, as well perhaps on what you expect to come from such an endeavor (usually in monetary values you may receive).
You might want to ask yourself - who actually makes money in music production endeavors?
Maybe you won't want to ask yourself.
Maybe it won't make any difference.
 

The presonus 22vsl seems to have better pre amps than the i2, 
The only reason I wouldn't buy any of these is they are all bus powered only with no option for using external power. 
None have SPDIF which I find essential. 
It's why I spent just a little more to get the 6i6 as it has a lot more going for it for on $50 more than the 2i4. A big plus is the Mix control software which is not included with 2i2 or 2i4. 
 
It's funny how most people like the pre amps. I do not. They are way to sensitive to small input changes. I find they are either to quiet or they overload easily. I use the SPDIF and the rear line level inputs so rarely use the mike pre amps. The units are well built with a solid case and the drivers are fair for the price point. This is not an RME but a lot less money so as the spaced out guy says, you do get what you pay for. 
A big plus for the Presonus gear is it comes with Software. Studio 1 would be a good value and you might find it useful. Focusrite come with a bunch of plugins of little value if none.