The relatively small JSE support services sector houses two of SA's most entrepreneurial companies. On the one end is Tokyo Sexwale's Mvelaphanda, in many eyes the company that has benefited the most from black economic empowerment (BEE). At the other is Brian Joffe's Bidvest, SA's most acquisitive group that, 20 years since its launch, looks set to break the R100bn turnover level in the 2007 financial year.

These corporations represent a significant investment opportunity but also carry some risk.

Mvela is at a turning point. Sexwale has made a (cautious) pitch for the presidency of SA. This could mean having to sever all links to the group.

Sexwale's charisma and political links have ensured many a BEE deal for Mvela.

Long-standing CEO Stephen Levenberg has also left the group to be replaced by Yolanda Cuba (29). At listed Mvela Resources, former Anglo American SA CEO Lazarus Zim has taken over the reins after buying a R1,1bn stake in the group and promising a wave of new deal flows.

The injection of fresh leadership is perhaps the necessary tonic for the group to extract greater value from its rather passive portfolio of investments. The market continues to trade Mvela shares at a discount of up to 25% of net asset value (NAV), listed by the group as R14,07/share at the end of February.

There is probably little the group can do with its core investments - 11% of Absa via Batho Bonke in which it holds 49%, 10,8% in Group 5, 18% in Life Healthcare and 4,5% in transport group Unitrans - but it is sitting on a lot of cash.

The Mvela Resources deal boosted the cash coffers by R1,2bn; added to the expected R250m in cash flows from existing operations, Mvela could well find itself with R1,5bn by year-end.

The market is effectively discounting the cash pile and a clever investment over the next few months could lead to a strong re-rating of the stock. As it is, Mvela Resources under Zim looks a more entrepreneurial proposition than under Sexwale. Given Zim's strong links to Anglo, a number of potential ventures spring to mind, not least a BEE deal with the world's largest platinum miner Anglo Platinum. Mvela is a share to watch.

Joffe has never had to worry about being underrated. The market follows his every move, expects solid financial performances and usually gets them. SA's sixth-largest company and last remaining conglomerate (with more than 2 500 business units under its wing), Bidvest has offered consistent returns to shareholders. But the market is insatiable. Bidvest is a victim of its own success - it needs to make acquisitions continuously to keep growing. In one week in May the group bought four companies - fleet management group Viamax from Transnet for R1bn and three food service companies in Asia.

But the market wants something bigger, similar to the acquisition two years ago of motor group McCarthy, which now supplies about 20% of group turnover.

Aviation could be an avenue: Joffe last year bought a 20% share in Comair and is involved in running services at a number of airports. The Comair deal could become Bidvest's next landmark deal.

Even without one, Bidvest will grow and offer investors solid returns. But such is Joffe's reputation that more is expected of him.