I have been a happy owner of an Oral-B Triumph Professional Care 9000 electronic toothbrush for 16 years. Using a YouTube-video I disassembled it once, with great difficulty, and replaced the battery. However, once again after many more years the battery is on the fade and I decided it was unwise to take it apart a second time and hope for it to still be water tight, so I purchased a new Oral-B, this time the Oral B Smart 1500. I selected it from the numerous confusingly similar models Braun offers as the one that had among the least features. I don’t need a blue-toothed toothbrush or the many other bells and whistles they promote; brushing my teeth shouldn’t be that complicated.I was curious to get my new toothbrush and see what had changed in 16 years. The news is generally good. See the photo for a comparison of the new version (left) and old version (right). The 1500 is smaller and lighter (4.5 oz vs. 6.5 oz) but it is buzzier and noisier, however not excessively so. The sound level of the 1500 is about 70 dBA in high speed mode when measured at 3”, and about 2 dB quieter in the lower speed mode. My older 9000 is about 2 dB quieter than the 1500’s lower-speed values. The older one had a nice soft over-molding on the front and back, that can be seen in the photos. The newer has only a small area of over molding on the front around the control button but the 1500’s back is dimpled. All in all, the 1500 is easy to hold and in fact feels better in my hand than the older model. Pleasantly the same brush heads fit both models.On a balance, I prefer the new toothbrush and enjoy using it. It has three brush modes, described in the manual as daily clean, sensitive, and whitening, that seem to essentially be high speed, low speed, and pulsed. I find the low speed most similar to what I was used to with the older model. Also, at age 71, I am aware of possible gum recession so I think I will stick with the slower mode.Of course the new 1500 has lithium batteries which the older model did not. I have tested the battery in the 1500 one time by using the brush until the low-charge indicator light came on. I could have probably brushed even longer but it isn’t good to totally discharge lithium batteries. I brush the full 2 minutes and an extra minute or so for my gums, roof of my mouth and tongue, or about 3 minutes, but only 1x/day. The other times I use a manual brush. Oral B says the battery should last about a week, which at their recommended 2x/day, 2 minutes each, would come to 28 minutes of use. I found that I got 20 days on my program or about 60 minutes of use. That comfortably exceeds their claim, but I was using slow speed and perhaps on high-speed the run time is reduced.I am careful with the pressure I bring to bear on my gums so I brush lightly. But I wanted to see how well the red warning light, indicating too much brush pressure, worked so I purposely forcefully pressed the brush head against the tops of my molars. The light does indeed come on, but the pressure I had to use was way above anything I would normally use while brushing.Finally, I want to share a tip for those of you who might not read the owner’s manual. To turn off the brush without having to cycle through all three modes, you can just press and hold the button until it shuts off.Bottom line – I like the 1500 and am happy with my purchase.