Stronger, Higher Quality DI's. How do ?

I've been wondering whether it makes any difference if I'd use the AR-133 in place of the instrument inputs of my Saffire Pro 40. Should I get it for recording direct guitar and bass?

I'm using AR-133 DI in place of my FF400 inputs, it sounds better IMO.
 
Hi guys..can someone gives an opinion about this direct box please??palmer pan 02 and boss DI 1 and radial pro 48 please?are they valid direct box??thank you very much..