A strong set of first half results from Frankie & Benny's and Chiquito owner Restaurant Group prompted Altium Securities to lift its target price on the restaurant chain operator to 240p from 200p.Pre-tax profits climbed to £21.7m from £21.1m over the same period the previous year. Revenues climbed to £210.1m from £203.2m, but were down by 3.5% on a like-for-like basis, which excludes the impact of new outlets.'These results provide increased confidence that Restaurant Group is significantly outperforming a challenging market, debt reduction is ahead of expectations,' the broker said.It keeps its 'buy' rating on the stock.Shares in Heritage Oil took a knock after the firm announced that a probe by the Financial Standards Authority (FSA) could hinder its proposed merger with Turkey's Genel Energy International, but broker Cazenove is unfazed by the potential stumbling block.It is too early to speculate on the outcome and Heritage's management is still confident it will go ahead, notes Cazenove, which is keeping its 'outperform' rating on the stock.'No one from Heritage is being investigated by the FSA,' the broker notes.'Whilst we do not have any details as to which members of Genel's operational team are being investigated, we note that the proposed merger could presumably go ahead without them.'Besides, Heritage still has 'world class' assets in Uganda and Kurdistan, Heritage notes.Online gaming giant PartyGaming saw pre-tax profits rise at the half year stage, but revenues fell by 21% and broker Collins Stewart remains unconvinced on the stock's prospects.The firm's revenues were hit by the appreciation in the US dollar, which was responsible for about half of the year-on-year decrease, as well as competitive pressures in poker and the consumer downturn.Collins Stewart retains its 'sell' rating on the stock, with a 120p price target.