WTB 52-55 Road/Tri Bike - $400 max

Looking for 2 bikes for a friend and his son who have just started duathlons. Son is borrowing my 55cm Kestrel Talon which seems to fit him pretty well, dad is a little shorter. San Antonio/Austin area, will travel to Dallas or Houston for a good deal. $400 each max price, they want to be sure they are going to like it before committing. Thanks!