The Old Bushmills Distillery attracts about 110,000 visitors a year. By contrast, the Guiness Storehouse in Dublin attracts more than 1 million a year – Ireland’s No. 1 international tourist attraction.

I was touring in Northern Ireland recently and visited the historic Old Bushmills Distillery plant in County Antrim. It was a so-so tour, but a few days later I toured the impressive Guinness Storehouse in Dublin, a fascinating and high-tech homage to hops, malt, yeast and water.

Both Bushmills and Guiness are brands of Diageo plc, the  multinational alcoholic beverages company based in London. It is the world’s largest distributor of premium alcoholic beverages, with an impressive list of brands: Johnnie Walker, Crown Royal, J&B, Windsor, Buchanan’s and Bushmills whiskies, Smirnoff, Ciroc and Ketel One vodkas, Baileys, Captain Morgan, Jose Cuervo, Tanqueray, Guinness … and more.

I have owned Diageo stock (ticker: DEO) in the past and sold it at a nice profit. The visit to Ireland left me with a strange thought: Would a 30-year investment in Diageo, with dividends reinvested, be a better investment than the 30-year TIPS about to be auctioned Oct. 18?

Why even think about this? The premise is an apples-and-oranges stretch, but I think it’s legitimate to  wonder whether buying a high-quality, dividend-paying stock (and reinvesting the dividends) might be a better investment today than a 30-year TIPS, which will pay just slightly over the rate of inflation over 30 years.

Although Diageo’s stock has been on quite a nice run lately, so have TIPS. Neither is ‘cheap’ at current prices. Here is a chart comparing Diageo’s 5-year stock price to the TIP ETF:

The TIP ETF, shown in blue, is up about 20% over the last five years, slightly trailing the performance of Diageo, shown in red. But Diageo has been much more volatile.

Safety. The TIPS completely wins on this measure. A buyer of a Treasury Inflation Protected Security will get his principal back, plus the inflation adjustment, if the TIPS is held to maturity. But if the buyer decides to sell within 30 years, there is a real possibility  that this TIPS will be worth sharply less (even 15-20% less) on the secondary market in coming years.

Diageo’s safety comes with its rock-solid brands of an ‘addictive’ nature and a growing market across the world. But it will be a volatile ride; the chart above shows how Diageo’s stock price plummeted 50% during the financial crisis. In 30 years, what are the chances of corporate mismanagement, accounting fraud, etc.? It is a risk.

Return. The 30-year TIPS will probably auction with a yield about 0.38% above inflation. If inflation runs 2.2% in the next year, the return will be 2.58%. Diageo currently yields 3%, so in the short term Diageo is likely to provide a greater return. The TIPS could yield substantially more in future years if inflation rises, but that is an unknown.

Taxes. Diageo’s dividend will likely be taxed at a lower rate – currently 15% – but that also could change in the future. In addition, a future sale of the stock may get preferable tax treatment. The TIPS interest and inflation adjustment is taxable as income in the year earned, which is a disadvantage. But there is no state income tax.

Reinvesting dividends. The key to my premise was to compare the two investments held over 30 years, with dividends reinvested. In the case of the TIPS, the interest earnings can’t be directly reinvested, but the inflation adjustment adds to the principal. Diageo’s dividends have been steadily increasing – from about $1.25 a share in 2000 to about $2.75 a share in 2012.

If that dividend continues to increase, DEO is likely to outperform the 30-year TIPS, by a wide margin.

But it is a much more risky investment.

At the moment, I probably won’t buy either.

Diageo is fairly pricey right now at $113.94 a share, selling at a P/E ratio of 22.95 for trailing-year profits. But it is expected to earn about $6.49 a share in in the current fiscal year, and $7.25 a share in the next, bringing the P/E down to a reasonable 15.7.

Something to think about in days of ultra-low yields.