Mine had a few Isla Bike Luaths in all the sizes from a club and I was not overly impressed tbh, and I tend to agree with Boris about the hype. They are not road bikes as such but cyclocross style bikes, and while this makes them a bit more flexible in terms of terrain, fitting mudguards etc, the cantilever brakes can be a bit troublesome compared to dual pivot. The rear mech is a mountain bike one. Generally I don't think the spec level justifies the price, although as others have said they consistently fetch bizarre prices on
Ebay, so you may get most if not all of your money back!!
One thing we found was that the brake levers on the tops (pretty standard on cyclocross bikes) encouraged the kids to ride with their hands on the tops instead of learning to use the hoods and the drops, which is a bad habit to get into, and really defeats the object of having a road bike, so watch out for that.
The
Decathlon range is worth a look, he may fit one of the smaller 700 cc ones - the Triban 3 or 5 both look like good bikes. We didn't get one for my lad in the end as we wanted 10 speed gears so he could easily use my wheels as spares at races, but they seem excellent value.
You can make quite a difference to the reach by fitting a shorter stem, and playing with the spacers on the headset, and its easy to change as they grow. Shimano Brake levers have reach adjustment.