I'm thinking of getting all 'modern' with my approach

[400bhp]

Aha, therein lies the problem. I'm not remotely interested in "pushing myself". Exactly the opposite in fact. I'm only interested in knowing that I'm doing the distance, in the most efficient way possible. It's like remapping cars. Some are remapped for all out balls out speed, and some are remapped purely to squeeze maximum MPG. Think of it like 'hyper mileing' in a car. I'm just interested in increasing my MPG, if any speed increases happen, that's a by product, not my aim.
Other than determining FTP, in scientifically controlled conditions, it would be a cold day in hell, synchronised with a deep blue moon, before I'll go anywhere near a Turbo Trainer, or any sort of indoor cycling.

Then you are pushing yourself, just in a different way. You still need to know your FTP.

And, crucially, you need to decide what"efficient" means for you? Is it achieving (say) 100 miles at 15 mph using as little energy as possible, or achieving (say) 100 miles using a certain level of energy in the quickest time? These are potential meanings for efficiency, both of which from using a PM and determining your FTP at the outset.

 

[mattobrien]

Aha, therein lies the problem. I'm not remotely interested in "pushing myself". Exactly the opposite in fact. I'm only interested in knowing that I'm doing the distance, in the most efficient way possible.

Then I am not sure that a power meter would be the best investment to help you achieve your goals.

 

[Racing roadkill]

Then you are pushing yourself, just in a different way. You still need to know your FTP.

And, crucially, you need to decide what"efficient" means for you? Is it achieving (say) 100 miles at 15 mph using as little energy as possible, or achieving (say) 100 miles using a certain level of energy in the quickest time? These are potential meanings for efficiency, both of which from using a PM and determining your FTP at the outset.

Exactly right. It's the former in my case, hence the reason for the PM. If I've got an actual scientifically determined number to work on, and a number on a screen I can reference, whilst riding, it makes everything neater.

 

[Racing roadkill]

Then I am not sure that a power meter would be the best investment to help you achieve your goals.

Completey wrong. Without the PM, I don't have a nailed on figure to work with, if I don't know the FTP, I can't determine the 56-75% of that number, the window of which is where I need to be, and where the best bit of the window is for me personally, to get round most effectively. I realise that a large majority of the power meters are bought by the 'Faux pro' brigade, who seem obsessed with how quickly they can go, but that is the thing I most dislike about cycling. I care not a jot about using cycling as a sport, I'm trying to get places, without having to spend much, avoid parking charges / congestion charges etc, and prefer to do it without knackering myself any more than I absolutely have to. The further I can go, the happier I am. I'm also not remotely interested in 'ultra cycling wossnames' either, again it's using cycling for a purpose that's of no interest to me.

 

[mattobrien]

Completey wrong. Without the PM, I don't have a nailed on figure to work with, if I don't know the FTP, I can't determine the 56-75% of that number, the window of which is where I need to be, and where the best bit of the window is for me personally, to get round most effectively. I realise that a large majority of the power meters are bought by the 'Faux pro' brigade, who seem obsessed with how quickly they can go, but that is the thing I most dislike about cycling. I care not a jot about using cycling as a sport, I'm trying to get places, without having to spend much, avoid parking charges / congestion charges etc, and prefer to do it without knackering myself any more than I absolutely have to. The further I can go, the happier I am. I'm also not remotely interested in 'ultra cycling wossnames' either, again it's using cycling for a purpose that's of no interest to me.

Would an HRM not allow you to ride to your HR zone and in an equally efficient manner? I appreciate the lag between power and HR, but if endurance and efficiency are an objective, and HRM may prove to be a lower cost option to help achieve this. That said, it's your money and if you can, why not have both.

 

[Racing roadkill]

Would an HRM not allow you to ride to your HR zone and in an equally efficient manner? I appreciate the lag between power and HR, but if endurance and efficiency are an objective, and HRM may prove to be a lower cost option to help achieve this. That said, it's your money and if you can, why not have both.

Quite. I like numbers