I always recommend and mainly install Worcester Combi boilers as they are a robust boiler with reliability and efficient performance. it would be a better investment to go with a Worcester in my opinion.
I Install many glow Worm Combi boilers each year, things I like with this combi boiler is that It is compatible with a plug in analogue or digital timer, or wireless digital controls, offering a good range of flexible options for controlling your heating.
I own a Vaillant Combi boiler that both provide my central heating and hot water for domestic purposes. The Vaillant series boilers are the choice of many installers all across the UK, they are undoubtedly the best main stream boilers on the market.