United Airlines has, somewhat quietly, launched a sale for mileage-based upgrades into BusinessFirst on most routes the carrier flies. Passengers can save 20% off both the miles and any cash co-pay required on travel between the US-49 or Canada and Europe, Japan, North Asia, Middle East, Central/Southern Africa or Southern South America. This promotion applies only for upgrades requested online through July 28, 2012. Even if the request is waitlisted due to no award inventory available at the time of request the discount will apply.
The notable destinations which are excluded from this promotion are Hong Kong, Ho Chi Minh City, Bangkok and Taipei. All destinations in North America, the Caribbean and northern South America are also excluded, though these are not routes marketed with BusinessFirst service so less surprise there.
The discounts are nice but it is still a stretch to consider cash+miles upgrades a decent value.
Miles plus copay is bad deal considering out of pocket cash if compared to a Saver Award but if you want to fly Business it is certainly the cheapest way sans GPU given the appropriate inventory.
Cash + miles is definitely cheaper than buying full-fare business, to be certain. But, depending on travel patterns and timings and routes, there may also be options like discounted business class flights which are cheaper than the cash + miles option in the end. On a round-trip ticket where the fare is $800, the co-pay is $1100 and there are 40,000 miles required, for example, a $3,000 biz ticket actually isn’t such a horrible value.
There are times where cash + miles doesn’t completely suck, but they are, IMO, few and far between.