Larzz, I'm in the same position as you, as I am, too, a Spanish otaku
though I live in Berlin now.
It's wise of you to wait for more affordable manga-reading 9 inchers: it's possible, but very hard to read manga comfortably in a 6 inch display. Manga books in Spain (the normal sort) tend to be around 8 inches in size.
That said, I admit I'm very, very fond of my Pocketbook 360. It works very fast, it swallows whatever file you put into it (even PDF's are decently read) and I love the design as I can operate it with both hands perfectly (while eating, for example :P). Plus, it supports as many folders as you wish to put in it, and you can put dictionaries on it, even make them yourself if you're familiar with the format in which they're made.
It is more expensive, too, but you must count that you actually do have a cover included in the price (the snap-on cover) which works very well, saving my PB more than once from my mistreating :P
There is an additional leather cover at your disposal as well in Pocketgoods, 29 euro (I bought it, but it was just my otaku-collector nature :P).
By the way, if you only want to read text, you can spare yourself the 6 inch displays if you want. 5 inch readers can display text in enough text sizes for you to find the proper one, and they're more portable.
As you may know, the Sony readers can be perfectly charged with Sony PSP chargers, which are on sale in Spain, so you shouldn't be worried about charging it.
Concerning the Opus, its owners are usually very happy with it and the design is nice too, but it seems that Bookeen is not very consumer-friendly, as it has taken a very long time for them to release sorely needed firmware updates.