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CX flight will be on their 2-class regional configuration A330 aircraft. In business class I would looking for a D or G seat, row is not critical. Bulkhead is a personal preference - some like them and some don't.
For economy, if travelling alone I would be going for a D or G seat and hoping E and/or F is free. If travelling as a party of 3, then perhaps go for D, E and G seats? It really does not make a lot of difference and just go for the personal preference of window vs aisle. I always look for as far forward as possible.