Why would you feel that I am fooling myself? The differences are very obvious. I have to wonder why you are so adamant to not trust my personal experiences. I am not holding dear a conspiracy theory or attacking anybody or anything. I even had forgotten that I had switched cards and was trying to figure out why things sounded so, what I considered, "bad" based on what I was used to hearing. To me that pretty much nails it to me that I'm not fooling myself.

We are dancing in a circle and I am dizzy. I'm gonna sit down and take a breather.

 

OP was asking for buying advice. It actually does matter what people say. No need to take it personally but I'm not here just to agree with people. And I imagine neither are you.

And still, I think it is entirely possible that you are just fooling yourself. Your somewhat changing story does not change that.

 

Of course I am feeling a bit side swiped as you are doubting my veracity. Mine is not a changing story, Yesterday before I packed up for two weeks away from home, (I procured a laptop for a mini traveling rig to record out in nature during our vacation time and will use the Focusrite instead of the Babyface as my computer has a hissy fit every time it is disconnected and reconnected...it is a real PITA) turned on the computer and DAW to jot down an idea on acoustic guitar and vocal and had my, at least to me, revealing experience and confirmation that I absolutely hear a difference in these two sound cards, the Babyface and the Saffire 6 USB.

 

Quality hardware will not magically make everything you do significantly better, but it can give you the headroom so that your skills can catch up with your hardware quality. Buy too low quality and you hit the ceiling real fast as your skills improve.

I bought an inexpensive 2 in x 2 out audio interface (sub $150) many years ago and it made a BIG difference to my options compared to onboard computer 3.5mm jack. But now I see its limits. An expensive interface may have been underappreciated when I was not skilled enough to recognize its benefits.

Now I can justify the investment in a higher quality interface, but I will have bought twice. Buying higher quality up front can keep you from having to buy again later. It all depends on what your wallet (and wife) allow.