I think Suzuki would face the same problems as Kaw did with 14R. More output generating just that much more heat and not cooking the engine or the rider. I think that's where Suzukis at it would require significant re-engineering to deal with these issues. Kawasaki took the plunge and it was much more effort than adding a 2nd radiator fan and punching out the motor (in fact I believe Kaw increased stroke not bore). Have to get more air and fuel in and out too. Is it worth it to Suzuki to do the same? Could Suzuki only match 14R or could they surpass it? Frankly if they can only catch up not sure it's worth it.
IMO for your average buyer they should just go with whichever make they prefer as far as the big bore bikes (well, Busa/14). I mean yeah, chances are at the drag strip with basically stock bikes, given riders of equal skill and weight 14R is going to win most of the time with only rider error being the real factor. On the street it comes down to who's probably practiced or the most experienced, weight, and balls.
I do recall reading something a while ago about Suzuki's engine design being better for modifications. It was something to do with the cylinders and heads or maybe just the heads. So for serious racing, which granted is a very small market share, Busa may still hold some advantage.