I'm in the process of switching from oil-fired forced hot water baseboard heat and electric DHW to natural gas. I've decided to go with a wall-mounted high efficiency modulating/condensing boiler that also heats an indirect HW tank. I've received quotes from five different contractors and after hours of Internet research (including this forum), I've narrowed my choice down to two mod/con boilers: Buderus GB142 and Viessmann Vitodens 100.
In general, I know both companies have impeccable reputations, with Viessmann regarded as just a tiny bit better. However, I've read some comments specifically about the Vitodens 100 model that have me concerned about it's quality and reliability. Most of the negative comments originate in the UK, where the Vitodens has been installed longer, and I'm hoping Viessmann has ironed out any defects in the meantime. On the other hand, I've seen virtually nothing negative about the Buderus GB142.
In the quotes I've received, the Buderus solutions are 6-10% more expensive than the Viessmann package. I know that doesn't sound like much, but I'm already stretching my budget. I'm concerned that Viessmann may have cut corners when they introduced the low-end budget Vitodens 100, and the Buderus may be a better choice for just a bit more money.
Can anyone with direct experience installing or using the Vitodens 100 comment on its reliability? I know any comparison between these models raises the long-standing stainless steel vs. aluminum heat exchanger debate, but until there's some hard historical data, I'm ignoring that point. I'm also interested in manufacturing support for diagnosing problems and getting spares out for both companies. I live in Massachusetts, pretty much halfway between the Buderus facility in Londonderry New Hampshire and the Viessmann facility in Warwick Rhode Island, so it may be a wash for me.
Please, no comments on any other boiler manufacturers - I'm focused on Buderus and Viessmann.