I enjoy using the Oral-B Smartseries 5000. In addition, I have a slim Oral-B Pulsonic that I use when traveling. I also have an Oral-B Professional Care 3000 that does a decent job of cleaning. Its brush head is smaller and less effective than the 5000's, and it has only 3 modes rather than 5 and doesn't come with a SmartGuide™. The 5000 is less bulky and seems to hold a charge longer as well, nearly 2 weeks. Aside from that, they are fairly similar. They both pause when it is time to move to a new brushing zone and have the pressure sensor that lights a red LED when you press too hard.
There are a few quibbles. The pause that lets me know I need to change where I'm brushing is a bit too long, esp. when it reaches 3 pulses. It is louder than Sonicare electric toothbrushes though not as noisy as the Pulsonic or 3000 model. The travel case is bulky and somewhat unnecessary if you don't plan to use it when traveling. I don't use the SmartGuide but I can see how it may be helpful to young children when brushing and may add a bit of fun to the process. Personally, I'd rather save a little money and just get the brush. Speaking of cost, replacement brush heads are rather expensive as well.
I find it easier to get a thorough brushing with a powered toothbrush. A standard manual brush can work too too, but it takes less effort when using a brush like the 5000. In the past I used a Philips Sonicare HealthyWhite R732 and I have to give the cleaning edge to the Sonicare. But the Smartseries 5000 is still an effective cleaning tool for someone willing to invest a bit in their oral hygiene.