FWIW we've been using the mortar platform to run large pig jobs without a fuss at http://datadog.com and we've been very happy with it. Glad to see them contribute their recommender code too.
Can you please suggest why you need a recommendation engine for datadog?
We don't use the recommendation engine but the underlying platform, which makes it really simple to write and run pig jobs. Though the majority of our business deals with real-time data processing, the ability to crunch numbers in batch without dev or ops overhead is attractive and well worth the price to us.