adjective
BAD : Before I actually started to use one, I was suspicious about the value of computers.
GOOD : Before I actually started to use one, I was sceptical about the value of computers.
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suspicious = thinking that someone may be guilty of doing something wrong: 'I started to get suspicious when he refused to tell me where he had been.'
sceptical = tending not to believe what people say about something: 'Many doctors remain highly sceptical about the value of alternative medicine.'