I don’t claim to have the investment acumen or anything close to the success story of Warren Buffett. But like the legendary investor, my favorite holding period is forever.

That fact is easy to discern from the MLP Profits Portfolio tables, which still feature seven of the Holdings from our very first issue in May 2009. One of these is the stellar Sunoco Logistics Partners LP (NYSE: SXL), which has returned 250 percent since our initial recommendation. That includes better than 30 percent thus far in 2012.

Unfortunately, over the past year or so except for brief stretches our view has been that units of the owner and operator of refined crude oil pipelines and terminals have been well overvalued.

And up to now the MLP has been able to live up to the lofty expectations in its unit price, parlaying consistent asset growth into distribution growth.

The 9.9 percent boost in the Aug. 14, 2012, payment from the May 15 disbursement was the most explosive increase in many months. And with Sunoco Logistics’ yield now just 3.8 percent, it appears investors are expecting even more ahead.

That may well prove to be the case. The MLP’s general partner is now MLP Profits Growth Holding Energy Transfer Partners LP (NYSE: ETP), and the latter plans to devote substantially all of its discretionary capital budget to expanding energy liquids midstream assets, which are Sunoco Logistics’ specialty.

On the other hand, if those sky-high expectations are disappointed in the least it doesn’t take too much imagination to see Sunoco Logistics’ unit price slide back toward USD40.

And as we already own the much cheaper priced GP–which garners the lion’s share of profit from future growth–it’s time to take our money off the table and move on to something more attractive.

My top choice for a conservative replacement is Oiltanking Partners LP (NYSE: OILT), which I featured in a Sector Spotlight in the October issue.

The owner and operator of terminals, storage and transportation assets for refined petroleum and liquefied petroleum gas in the upper Gulf Coast officially became a Conservative Holding on Nov. 1, when it cut below my target of USD35.

The unit price actually hit a low of USD33.71 that day before rebounding back over USD35 later in the week. The only hard news over the past month was a larger-than-expected distribution increase to a new rate of USD0.375, effective with the Nov. 14 payment.

The ex-dividend date of Oct. 31 was too early for MLP Profits investors following my advice on entry to collect this payment. But the 4.2 percent increase from the Aug. 14 payment is the fourth consecutive quarterly boost for Oiltanking Partners and a sharp acceleration from the previous quarter’s growth rate of 2.9 percent.

As I make clear in the In Focus feature, we don’t generally recommend MLP IPOs until there’s at least some trading and distribution paying history. I want to see some proof that what’s being offered has staying power on its own, and that the issuer hasn’t set the price to capture the benefit of pre-deal hype.

In the case of Oiltanking Partners, it’s proven every bit as solid as initially advertised. And given the acceleration of distribution growth, I fully expect to see that affirmed when the MLP reports its third-quarter results later this week.

The price of not buying at the initial IPO is we have to pay more. But now roughly 15 percent off its September high, Oiltanking Partners is fairly priced to the double-digit distribution growth it looks set to achieve in what may be the highest-percentage business in America now: facilitating the movement to market for the unfolding US production oil boom.

Oiltanking Partners is a buy up to USD36 for those who didn’t get in with this month’s initial entry.