ahh ffs it will be fine! Lots of people hate paypal for several reasons:
It's ****
It's expensive
Buyer protection is ****
It's ****
Cheques may be slow but the buyer pays the stamp, you have an actual address to go to.
The bloke has 20 feedback, all positive, more than you.
Cheques are easily traced through the bank.
Nobody would bother for £100 to rip you off, especially given a cheque
You will have an address for him
The item he is sellling is not out of sync with everything else he has sold/is selling.