Replacing a complete uPVC front door lock

[superstardeejay]

I'm trying to upgrade my front door lock...it's an 80's style uPVC door with a 4-point-plus-latch (roller only) lock (made by Ferco) that extends the length of the door. I fitted an anti snap cylinder a few years ago.
I want to fit a complete new lock with a shootbolt or hook, I don't trust roller-only systems in plastic doors as I believe a good shove by a rugby-player type and the rollers will shear.

How easy is it to convert to something more substantial? I'm happy to drill or mill the door to accomodate a new lock, and the same with the roller keepers in the frame. Can anyone recommend a good lock?

 

[crank39]

Locks are all pretty much of a muchness, just get one with at least 2 claws/hooks, 4 is better though, my personal pref is winkhaus but there are others

Just make sure you get the correct backset, most are 35mm now but old doors could be anything from 30/35/40 or 45mm

If your willing to drill the door then the PZ won't be as critical, most modern doors now are 92mm but older doors were much smaller, if you have one of those its matters not as a new 92pz handle will cover your old holes, just won't cover them if you get the wrong backset

 

[superstardeejay]

What's worrying me is that although the door locks themselves seem fairly standard, when I look at the frame profiles, they all seem different! I have various upvc doors at home and at work and no two are the same.

The keeps for example all seem machined to fit around the nibs and recesses in the extrusions, yet wholesale lock suppliers seem to offer 'generic' or 'general purpose' keeps. I'm confused by it! Obviously I could cut or rout the frame profile to suit the hook/bolt keeps but these are sure;ly integral to the strength of the lock system as a whole?