Hey now.
I raced my Fuji Cross in crits last year Cat 3/4 and 4s and during sloppy weather training races. I set it up with 700 x 23s. I tworked fine and I plan to do the same this year, except this year for the spring slop, rain, training races I put on a road crankset 54/39 oppossed to the 46/38 from the cross and I have a 12/23 or 25 in the rear. It works great. As others have said, the braking is not as good but it is good enough. I love riding this bike and ride it on the trainer, etc. When cross season comes I go back to the cross crankset and throw on some cross tires.
With a limited budget you get the best of both worlds.
+1 on the Fuji Cross. The Cross comp is great and comes in around 20 -21 lbs and could be lighteredwith some minimal changes to wheelset (Mavic OP with ultegra). My bike weighed 20lbs with the old Ritchey Cranks/bb and heavier wheels. Now it is under 20 around 19. Can't tell the difference. As long as the tires go round it will be great for cross. Oh, I also switch the pedals and shoes during cross. Look and road for road riding and Time and Nike Carini mtb shoes for cross.
Good luck.