My Bosch is twelve years old, has never needed a service cal
I have a 300-series (entry level) with hidden controls. In 2001 this was known as the "Integra design" line. They had the same features as the front control panel 300-series machines but cost somewhat more because of the hidden controls/plain front panel. This was pre-Ascenta. The front-panel 300 model was just under $500, my machine cost $600.
There were two 300-level versions, one had PowerScrubPlus/Normal/Rinse-Hold, the other had PowerScrubPlus/Normal/Quick Wash. I have the latter model and am happy that I do, because the machine cleans so well (even if I take a week to fill it) that Rinse/Hold isn't necessary, and sometimes Quick Wash is adequate for lightly soiled loads (like having people over for coffee and snacks). Quick Wash is also useful for cleaning items other than flatware, glasses, or dishes (see below on how I clean my refrigerator storage bins). Quick Wash is only 30 minutes, some companies label their 30 minute cycle as "Party" cycle to emphasize its usefulness in entertaining.
From inspecting Ascenta models in the store and from reading their specs on the Bosch website, there are two differences that I have noticed:
1. The bottom of the tub (in the models I have seen in person) is plastic rather than steel. The sides/back/top are steel. The main function of a steel interior is not to look pretty or to last longer than plastic, but to provide a surface for the water evaporation off your plates to condense. The high temperature of the final rinse will hasten this process<span style="text-decoration: underline;"> as long as you use a rinse agent (Jet Dry or equivalent) </span> . At the end of the cycle, your dishes will be dry, but the tub sides will be wet---this is normal operation for this machine. Bosch does not have a "heated drying" option and there is no exposed heating element.
2. The Ascenta machines appear to operate at higher decibel levels than the 300/500/800 series and presumably they didn't spend as much money on soundproofing. My 2001 model 300 series was rated at 52 dB back then which is equivalent to today's Ascenta models (making me think that the amount of soundproofing used on my machine is equivalent to what they do on today's Ascentas) and it's plenty quiet. I could hold a card game in the kitchen. It seems that today's 300/500/800 series now run in the mid to upper 40s dB range, quieter than the previous generation.
My qualm with Ascenta would be the long-term durability of the plastic-steel junction at the bottom of the tub. Would it ever separate or leak in the long run? I don't know that it would, and Ascenta has been around long enough (five years?) that you'd think someone on this site would have posted information on the long-term reliability of the tub. CR gives great reviews but their testing does not follow the machines for ten years (and in this case, since there is a cost-saving innovation in the tub, which is a departure from traditional Bosch design, I'd want to know long term data on that tub).
What is nice to know is that CR's testing shows Ascenta and 800 Bosch models coming in at 80-81 on their rating system. (what is odd is that the 300s and 500s had the same subjective ratings---two "excellents" and two "goods" but lower numerical scores). Ascenta got the "Best Buy" designation because "Best Buy" combines score with price. The high end Kenmores got ratings as high as 85, but at twice the price do not meet CR's "Best Buy" criteria----though they were rated as "recommended".
One feature I love about my current machine is the tall item sprinkler. The top rack comes out and the sprinkler attaches to the water outlet along the rear tub wall. Lets you wash large items in the lower rack, which for me means refrigerator shelves and bins, as well as large cookware like baking pans. Give them a Quick Wash and they look brand new again. My guess is that with the switch to third (cutlery) racks that new machines with the third rack no longer have the tall item capability. If Ascenta has retained the tall item sprinkler, that would be a reason for me to buy one, even if I weren't sure about the plastic/steel tub issue. The lower price would help ease concerns about tub durability. 52 dB is quiet enough for me.
