It's really just a 24-290 with a very mild teleconverter to enlarge the image circle so that it covers 5K on the Epic. Slight loss of speed from T2.8 to T3.2 which is the tradeoff. The 24-290 does cover 5K on the Epic down to about 35mm or so.
Typically the wide end of these zooms aren't used too often (go to a 17-80mm or 15-40mm lightweight instead) so in my opinion the 24-290 is not particularly at a disadvantage; it's still the workhorse zoom of choice. The 28-340 is a big investment that serves a smaller niche; that said, depending on your market and whether you think the 6K Dragon sensor will increase demand for larger image circle lenses, that may change your perspective.
Personally, 90% of my work is Alexa based which is a proper S35 sized chip, and half the jobs I work on with Epic shoot 4K anyway.