Richard - my experience is that some strings sound OK on some guitars and less OK on others, but I'll summarise what I use and why.

I play a Martin XC1T electro-acoustic with a Baggs iBeam pickup, and a Larrivée OM-03RE with a Baggs pickup, and I play these both electrically and acoustically.

When I bought the Martin, it was fitted with "Eric Clapton Martin phosphor bronze strings - .012-.054 gauge (I think). I have fairly acidic hands, and these would retain their brightness and zing for about a day. Now, some players don't do brightness and zing - preferring a duller sound - but not me. So the Martin strings had to go, and I decided to try both Elixir coated strings and D'Addario EXP coated strings.

The D'Addario's suit neither guitar nor me. They sound completely dull. I recently had the pickup in the Martin changed from Fishman Ellipse to the iBeam and the techie who did the change also put new strings on for me. He commented on the difference that the new Elixirs made when he took the not-so-old D'Addarios off. Much cleaner and less muddy.

The Larrivée came factory-fitted with Elixir Nanoweb Lite strings - .012-.053 gauge, and I've stuck with these ever since. When the coating starts to fray over the soundhole on the 3rd and 4th strings is when I change them - or when the 3rd string breaks. Elixir 3rds have a reputation for breaking early, and I now order 3rds by the half-dozen from my supplier. This breakage applies to both guitars and can happen at the nut or bridge ends. I wrote to Elixir in Germany about this recently. They wouldn't admit there was a fault, but sent me two complimentary sets... Polywebs just fray faster. However, in spite of these minor complaints, I still prefer Elixirs to any others at the moment. I will never use EXPs again.

My supplier has been recommending the new Ernie Ball coated strings as being very good, and I may well give these a go. However, it seems to me that any comment on strings will vary from player to player and from guitar to guitar - so experimentation with what suits you best seems to be the rule.