While credit cards and PayPal payments are probably the easiest and most convenient for a customer to use, not everyone will trust the Internet with their payment details and will instead prefer to use more old-fashioned methods. Ironically, a higher percentage of fraud is associated with check payments than with credit cards from online sales, but there you go.
Be careful with checks and money orders. Some banks will clear the funds in your account immediately when you deposit a check into your account. Acting on good faith, you then promptly deliver the product, only to find that the bank has removed the funds from your account once the check bounced and the customer has either maliciously or unwittingly left you out of pocket. Ouch!!
If you feel that your sales will be adversely affected due to the lack of other payment methods, then by all means, read on…