Peerblock does not appear to be actively developed. It was a fork of Peer Guardian and now it is forked into Bot Revolt which gets indifferent reviews.http://www.ghacks.net/2013/09/04/bot-revolt-peer-guardian-block-alternative-windows/ (read the comments).
The delivery platform doesnt matter much what matters is the ipfilterlist - IBlockList .
If you trust the list to be accurate and uptodate - good enough all the blocker program has to do is load reliably, update reliably and block the appropriate ip ranges. Peerblock seems to.
IBlocklist reviews well for effectiveness but users advise against the the paid product as once you have give your creditcard number they seem to find it hard not to use it like their own - many reports of having to stop the card. or refuse charges through bank.
Blockers only do part of the job. https://torrentfreak.com/anti-piracy-blocklists-dont-keep-bittorrent-spies-out-120904/ .
Even though VPN's will hand over your data (unless they explicitly dont keep records - which is illegal in e.g the UK. France and Australia) https://torrentfreak.com/which-vpn-services-take-your-anonymity-seriously-2014-edition-140315/
a combination of a peerblocker and a 'no record' vpn should prevent the MPAA etc from becoming interested in the first case.
If you pay for any of these services better to use bitcoin or giftcard / cash (the last two can be traced by federal agencies but not private agencies) .
I would feel moderately comfortable with peerblock (IblockList weekly update (free)) and the free version of Torguard and only downloading / sharing a few torrents at a time. The more you have seeding and longer the bigger target you are.
So yes peerblock as part of an integrated vpn and anonymous (or all free) payments and small target seeding policy should still protect you.