as a nice alternative, turn right at the shop in collingbourne ducis, follow road for a mile or so, to a T junction (The Shears pub dead ahead), turn left, it starts a bit narrow and then opens up onto the 'fair mile' a beautiful, open ridgeway, open it up and enjoy! It then gets nice and swoopy. You will automatically rejoin the main route at the A338 near Wilton Windmill.
be aware there are 2 speed cameras in Tidworth, and normally a patrol car as-well. But a fun ride for a sunny afternoon, also watch out for farm access and tank crossings if you continue though tidworth.
also if you leave tidworth and keep following all the way to malbrough its a slightly longer ride, but good fun and a bit of a cool down.
An entertaining road with plenty of fast corners and changing altitude. Pleasant views as the scenery opens out towards Salisbury Plain.