Integrated (or built in) appliances are common in many UK homes. They are desirable for many people with fitted kitchens. However, they do have a lot of downsides compared to free standing appliances. They look great because they hide behind cupboard doors. As far as I can see though there is no other advantage to them apart from that they are hidden.
There are several disadvantages to built in appliances –
- They commonly have smaller capacities due to them needing to fit into a confined space
- They cost more – usually considerably more
- There’s considerably less choice available
- They can be difficult to install
- Many engineers won’t repair them as they are often a real pain to get out and work on
- Many appliances can’t be pulled out without causing damage as tiles are commonly installed in front of them
Integrated appliances can be very hard to repair
I’ve been out to repair built in washing machines and dishwashers that have taken 25 minutes and a lot of struggle to just get out to look at. There’s a constant worry about damaging flooring or other parts of the kitchen units during the process. It’s also sometimes just as difficult to refit to the customer’s satisfaction with everything aligned properly. It has to be said that if installed properly it shouldn’t be that difficult, but a surprising amount of built in appliances are badly installed. This is why I and many other independent engineers wouldn’t go out to repair built in appliances. Repair charges on built in appliances are generally higher for these reasons.
Buying advice
The advice as to which built in appliance to buy should be roughly the same as with the free standing ones because the standard of the appliance shouldn’t be different from a manufacturer’s free standing appliance. For washing machines see Buy appliances advice and resources
Summary
If you have the space I would always go for free standing but I appreciate many people want built in appliances. However, built in choice is severely limited compared to free standing. For example, on one of the most popular online sites they (currently) sell 188 different free standing washing machines but just 22 built in. They also sell 292 free standing fridge freezers, but only 77 built in. Ovens and dishwashers tend to be less affected though as they tend to have roughly similar amounts of built in and free standing appliances to choose from.
Research. Don't waste money with bad purchases. Which? have an excellent no-strings trial offer - 
I recently installed a new Fridge freezer, washing machine and dishwasher into my son’s new kitchen after they understandably decided they wanted all their appliances hidden. My son and I took many hours and had many problems to overcome before we got them installed with the kitchen doors in front and the kick strips in place. It was worth the effort, they look great, but they are NOT easy to install and I would not fancy getting them out to repair in the future.