It’s been 12 months to forget for Lonmin (LSE: LMI), Premier Oil (LSE: PMO) and Ocado Group (LSE: OCDO). Even so, management at platinum miner Lonmin and oil producer Premier would surely love to be in the shoes of their peers at Ocado. Shares of the online grocer are down a mere 34% over the past year. But will value-hunting investors find any of these three shares a bargain buy at today’s prices?

Elusive growth

Betting against Ocado has certainly surpassed rugby as the sport of choice in the City these days with some 20% of all shares outstanding borrowed for short positions. Despite recently posting the 13th straight quarter of double-digit sales growth, investors are beginning to wonder if, not when, Ocado will have built up sufficient market share to jack up margins and sustain substantial profits.

With Amazon (through its November introduction of Amazon Pantry) and traditional grocers all fighting for market share in the growing online grocery market, Ocado will find plenty of competition and increasingly squeezed margins for the foreseeable future. While there are rumours of Amazon buying Ocado for its distribution network, I don’t believe rumours are reason enough to buy shares of Ocado.

Price problems

South African platinum miner Lonmin has been on life support for the past two years as platinum prices have dropped over 40%. The latest rights issue, which raised some $400m in November to pay down debt, has staved off the Grim Reaper for the time being. However, unless platinum prices rise substantially and quickly, share prices will remain bogged down in their current 40p to 60p range.

For the first nine months of 2015, the company was free cash flow negative to the tune of $167m. With only $770m in credit available, the company will be forced to continue selling platinum as fast as it can mine it to remain a going concern. The issue is that other large platinum miners in South Africa, the world’s largest producer by far, are in similarly bad shape so a dramatic rise in prices could be quite far away as supply remains high.

Premier promise

Shares of Premier Oil have been suspended for nearly two weeks now after the company announced the $120m acquisition of E.ON’s North Sea oil assets. This deal provides roughly 15,000 barrels a day and includes 64m barrels of proven reserves. While the deal makes sense from this perspective, the company still has net debt of roughly $2.2bn with $670m due over the next two years. However, cash and undrawn credit lines of $1.2bn do provide a significant cushion.

With high-priced hedges expiring and crude prices continuing to drop, it remains to be seen whether management forecasts of continued positive net cash flow will remain true in 2016. Either way, Premier’s balance sheet means it’s well positioned to ride out low prices over the medium term. The E.ON deal does also add significant assets at very low prices in Premier’s main geographic area. For long-term investors with high-risk appetite, I believe Premier Oil has significantly higher upside than either Lonmin or Ocado.  

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Ian Pierce has no position in any shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.