Master limited partnerships (MLPs) sure come with a lot to like … but it seems that Wall Street may be a little trigger happy in terms of rolling out new products that track the space.

Just this past January, two new MLP-based exchanged-traded funds hit the market: The Global X Junior MLP ETF (NYSE:MLPJ) and iPath S&P MLP ETN (NYSE:IMLP). That brought the total number of funds that track the midstream, shipping and other commodity-based firms that use the lucrative tax structure to 13.

Now, you can add another fund to that list.

Barclays (NYSE:BCS), which was also behind the IMLP, just announced the ETN+ Select MLP (NASDAQ:ATMP), which hopes to differentiate itself from the leaders in the MLP pack using a new index that screens for quality.

For investors, given the plethora of funds that already track the space — and with some already accumulating billions in assets and millions share per day trading volumes — the real question is whether or not ATMP is worth a spot in your portfolio.

Let’s take a look.

Branding

This new MLP-based exchange-traded note will hit the market in less than three months … but right off the bat, things seem a bit peculiar.

To start, ATMP will not be under the bank’s popular iPath umbrella of ETNs, but under its lesser known “ETN+” brand. The interesting thing about this is that Barclay’s actually moved several of the ETN+ notes over to iPath as way to drum-up “support” and assets for several struggling funds.

Plus, neither website — iPath nor ETN+ — makes any mention of its brother’s offerings … and most investors have no clue that Barclays even offers funds outside of the iPath line. With no real investor support, the fund could be done before it even gets started.

Holdings

Then again, branding doesn’t really determine performance; its index does.

ATMP will track the Atlantic Trust Select MLP Index — a benchmark that focuses on what the firm calls the “higher end of the MLP space.”  That basically means the stocks within the index are shown to have the highest credit rating quality. According to the prospectus, securities in ATMP must pass several screens that look for long-term credit rating, cash flows, market capitalization and trading volume.

While it is expected that the portfolio will include limited partnership interests in MLPs — such as Kinder Morgan Energy Partners (NYSE:KMP) — the fund can also include midstream general partners in the index, structured as both MLPs and corporations. That provides additional exposure to a fast-growing and attractive sub-sector in the energy infrastructure industry. The index also provides exposure to general partners of U.S. MLPs in Canada.

The index will be rebalanced quarterly and consist of a basket of between 20 and 100 MLPs meeting the high-credit criteria for inclusion in the index. ATMP will cap the maximum weight for LP interests at 8% and GP interests at 4%.

Top holdings on the LP side include Enterprise Products Partners (NYSE:EPD), Kinder Morgan Energy Partners and Plains All American (NYSE:PAA). On the GP side, top holdings include Enbridge (NYSE:ENB), Oneok (NYSE:OKE) and Kinder Morgan (NYSE:KMI).

Differentiation

That inclusion of general partners — the firms who sponsor the MLP, receive the tax advantages and juicy incentive distribution rights — is a unique twist in the space. All of the popular funds, including the $5.4 billion ALPS Alerian MLP ETF (NYSE:AMLP) are absent of GPs.

The addition of GPs has also helped Atlantic Trust Select MLP Index outperform its main rivals. The index was only created on Feb. 20, but Atlantic Trust did include hypothetical back-testing in the fund’s prospectus. From July of 2011 through February of 2013, ATMP’s index managed to produce a 13% return — besting the Alerian MLPs’ 8% return. It also managed to beat the midstream focused Alerian MLP Infrastructure — which can be played via the UBS E-TRACS Alerian MLP Infrastructure ETN (NYSE:MLPI) — by over two percentage points.

However, that weighting towards general partners does hurt in the income department. During that time, ATMP would have sported a 5.5% average dividend yield, while both the Alerian indexes would paid 6.2% and 6.3%, respectively. That could be an issue for some retirees looking strictly for “I need it now” cash flows and dividends, rather than total portfolio returns.

Another issue could be the funds high expenses. ATMP will be the most expense fund in the MLP category at 0.95%. Most average around 0.85%, with the Global X MLP ETF (NYSE:MLPA) costing the least at 0.45%.

Verdict

Aside from the curious branding, ATMP does look like it adds something unique to the MLP fund space. The inclusion of general partners — both corporate and LP — can add a curious twist for portfolios … and one that, according to back-testing, does lead to outperformance.

Unfortunately, given the size of the few behemoths in the sector, ATMP has a lot of catching up to do. The GP addition may not be enough to entice investors away from the other fund leaders in the space. Wait a bit before buying if you’re interested.

As of this writing, Aaron Levitt did not own a position in any of the aforementioned securities.