Crossroads - charity

Has anyone heard of this charity, not sure if its a national one or just local to our area. We've been told that we can organise for someone to come and spend some time with MIL who has dementia, she gets very lonely between 6 - 9pm. As we and SIL have her most days this is the only time we get off. They come recommended by social services, you can buy a voucher for £2.50 per hour and make the arrangements yourself for when you need cover. It sounds something that could be worthwhile wondered if anyone has any personal experiance of this charity.