I've been here an awful lot of times and some of those times the meals have been amazing. Other times they've merely been OK. And yet other times I've had to rethink my meal choice because they're simply out of ingredients.
I keep returning because the food is reliably OK and, about 75% of the time, amazing. Their noodle dishes are the biggest source of quality variability; sometimes the noodles are clearly overcooked (and thus challenging to separate from one another and eat because they're glued together) whereas in other cases they're done properly. The same with spicing: sometimes the 'hot' is super mild whereas in other instances it's appreciably warm in the back of your throat.
The staff are always friendly and accommodating, and have given me discounts when the cooks have been unable to fulfil an order. The servers are all quick with refills and provide helpful guidance to diners who are unsure of different items on the menu.
In terms of ambiance, the restaurant is tastefully decorated. It also tends to be pretty quiet in the evening and so a nice place to go with a friend or loved one for a quiet meal.
All in all, Thai House Cuisine is worth visiting if you're looking for a regularly decent meal and are in the area. That said, don't come to the Beaches just to visit this particular location.