Yes there is good upside on an acquisition basis for those who invest on anticipation of an acquisition and that's certainly a possibility with BCEI with its mostly contiguous acreage in the Niobrara and its history of unsettled management. ROSE had 979 mm boe 3p reserves and was acquired for total EV of $4bn. BCEI has 558 mm boe 3p reserves and, on a similar and full acquisition valuation, you get $2.5 bn which is 40% above the current $1.8bn EV.
Whilst the stock, at under $20, is attractive from an acquisition viewpoint it's still not entirely cheap on a 2016 forward earnings basis. Still, the downside from here ($20/share) is limited and if they can make $1.50 a share in 2017 the stock should rise to the mid $20s in the second half of this year. At under $20 I think it's a good buy even with flat oil prices. Any increase in oil prices in the next couple of years is a free bonus.