Speaking as someone with previous experience of breaking and entering (squatter rather than burglar but the skills are transferable to a degree) most anti climb deterrents are pretty ineffective against everyone but the most opportunistic thief. And the best deterrent against opportunistic thieves is to ensure that all your windows and doors are properly locked and anything valuable in your garden is nailed down.
Speaking as someone with previous experience of breaking and entering (squatter rather than burglar but the skills are transferable to a degree) most anti climb deterrents are pretty ineffective against everyone but the most opportunistic thief. And the best deterrent against opportunistic thieves is to ensure that all your windows and doors are properly locked and anything valuable in your garden is nailed down.