Not only should you expect the dwc plants to catch up to the soil plants you should expect them to quickly bypass growth rates in soil,as long as ph is good,water temps are 55 to 70 degrees,water is highly oxygenated & nutes are within acceptable ppm range for small plants your dwc plants will EXPLODE in growth,up to 12 inches in a single day.
If every condition is near perfect most forms of hydroponics can achive growth rates of up to a foot in a day,its way faster than soil.
My strain of sour deisel in soil takes 10.5 weeks to finish,the same strain in flood n drain takes 7.5 weeks to finish,thats a full 3 weeks faster.
Just be extremely aware of all conditions with the dwc,especially water temps,hydro plants will grow in warmer temp water but nowhere near as fast as colder temp water,same goes for low oxygen water,keep temps down and give em as many air stones as ya can & the competion between grow types is over,the dwc will smash the soil in growth rate.