Post the mega-merger announcement on Thursday evening - Kotak Mahindra - ING Vysya Bank deal - Deven Choksey of KR Choksey Securities advises investors to buy Kotak Mahindra Bank on every dip and stay invested for 2-3 years. He says the market cap of Kotak Mahindra Bank and  Axis Bank will be Rs 1 lakh crore and it is trading at half the price  State Bank of India is trading at. This one proposition becomes attractive for many to consider in the portfolio, he adds. He feels it makes sense for investors to invest in both Axis Bank and Kotal Mahindra Bank. Choksey, however, is not too enthused about the other major deal that happened yesterday.  Tech Mahindra signed a definitive agreement to acquire Lightbridge Communications Corporation (LCC), a global network services leader for an enterprise value of approximately USD 240 million, subject to regulatory approvals. Choksey says though the deal is topline accretive, it will contribute hardly 8 percent to margin. He is of the opinion that it will be better to wait for the management commentary before making a move on this company as he is unsure how much Tech M is willing to capitalize or invest in this market (network sevices). On the market as a whole, the next sector or companies that can perhaps take leadership as far as the Nifty is concerned is the oil and gas space. If crude oil price bounces back to USD 84 per barrel as is expected, then companies like  ONGC and  Reliance can take leadership positions, he believes. He also advises investors to also invest in large PSU banks such as State Bank of India and  Punjab National Bank as these banks are likely to benefit once credit growth revives and when rate cut becomes a reality. Also the stress on the books is coming down for SBI with NPA issues subsiding to an extent.