They were the most enjoyable to me, but i guess that depends on what you are looking for... I have very fond memories of grand canaria but have a feeling its because of personal reasons more than the place, but i have some great pics from GC, it has lots of sight seeing places, moreso that Lanzarote, which as i remember didnt have much...
Taking into account that my favourite holidays have a fantastic beach and a great bar where you can become friends with the locals, you may not go for what i did
Seeing as its well known as Sunny Fuerteventura I dont know where you heard that...
the yearly "low" is around 23 the "high" is around 30... not as hot as some places get, but pretty great all year round and it is a really beautiful place, my mum had her honeymoon there and still raves about it though she has a new favourite now that she visits 2 to 3 times a year... but thats not what you were asking so i'll shut up.
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