My Merrell Moabs arrived earlier this week and I first tested them yesterday evening on a 6mile walk through the Chiltern Hills. Very nice shoes, no need to walk them in or anything. I had boots before and had to "break" them in before they became comfy.
It wasn't very warm yesterday evening/night, but I had no sweaty feet. They claim to be waterproof, but I cannot say much about that yet.
Quite expensive for a trainer/boot, I hope they last a while.

One option to consider is trail running shoes. They tend to have a high level of padding, and a good heel counter.

The disadvantage is they do not last anywhere near as long as walking shoes. FWIW I have worn Saucony Xodus for several years.

It is worth going to an good quality boot fitters and expain the problem. If you are in the north Whalley Warm and Dry are good. They have a wide range of footbeds
Accilles tendon problems can morph into Plantar Fasciitis for which a good solid boot is best.
I do not know how much you already know but physiotherapists can often recommend useful exercises for these problems.
If I expect a blister or feel one coming I put vaseline on which usually stops further problems

Andy,
Everyone has different feet but...
From what you're saying, far more important than the footwear is a good footbed - are you just using the ones supplied?. They are squishy and grossly inadequate . There are a few makes of good ones that stabilize the feet in the correct position and, most importantly, are very firm at the rear to keep the heel in the correct cupped shape.
I use Superfeet, the Trailblazer variation. They have a firm cupped heel and support the arch too. Combined with lightweight footwear that suits the foot shape they're great.

If they suit your foot shape I can recommend Merrell Moabs, they are light and come in a shoe version and a mid-cut version. They have a wider than average toe box that generally suits British feet and excellent underfoot cushioning.

I haven't had a blister for over 20 years despite walking some very long days - I did Hadrian's Wall in the Moabs this year in 3½ days, among other trails, not a hint of a foot problem.

hi Andy, I always use zinc Oxide tape which I get from firstaid4 sport and go for 5cm x13.7 on my damaged Achilles. One of which is around three or four times as big as it should be . Cover you Achilles double and it should protect them. Personally I always wear boots as it gives me a higher back for protection of my ankles and damaged Achilles and having just walked the Pennine way I had no problems, I wore Scarpa boots.

I really need some recommendations/advice on hiking shoes. If I wear a boot for too long my Achilles kicks off (I love my Salomon 4d but after a couple of days need a rest) and an 'approach trainer' sets off deep blisters on the heels (because of the slight give). So really I need a sensible pair of shoes - but something that can handle fairly tough stuff (Dales Way/Harridans Wall). I've looked at the Brasher country shoes that seem to fit the bill but (irrationally) they look just a little too 'normal' - does anybody have any experience.

thanks