interesting that the lawyers that are trying to stur up the class action make no mention of the elephant in the room just a bunch of meaningless comparisons. that being said the price action sure puts pressure on the deal. i was well owned RNF so have my own baggage in the deal. As I recall I rode it up and then partway back down before bailing. UAN is unique it that it DOES NOT use natural gas for its feedstock. I believe it would make an interesting obviously bigger company but i think it would benefit RNF more than UAN. The biggest factor in all of this for the future is an increase in the price of corn. US AG is absolutely amazing, the last figures that I saw was about 40% of the crop going to green energy (uck even if it is good for me, isn't everyone in the govts pocket one way or another so i might as well have mine til we go broke of course) and we still have a surplus and $4 a bushel. The good land here has backed off from 10K plus to about 8K here in the corn state, still a far cry from the slump of the 80's when we were about 1K per acre.
depending on your hassel level and how much you buy positive UBTI may not be a big deal to you. You get $1000 total per IRA account, cannot subtract the negatives from different stocks. The custodian figures the tax if above the $1000 and may charge you for the work, best to check before you buy large amounts. I have done several MLPs in the three accounts that I have for several years and have never had a problem but it is definitely a possibility and always a first time. From my point of view no big deal, primarly after dividends and distributions at this stage.
Not trying to offend anyone here but STON does not pay dividends, they pay distributions. As an MLP they can show a loss and still pay distributiions and many MLPs do that year after year. Granted much better to make a profit then they can increase the distribution. A concern for the IRA investor is their UBTI which if high enough makes the distribution taxable even in an IRA, too big a subject to cover here.