Rocky Mountain Saddle Bags
 

Did anyone try those for a long trip , they seems nice and use many other products from the same company so I am interested even so they seems pricy.

Here is the spec
Rocky Mountain Saddle Bags - Motorcycle Saddle Bag by Wolfman Luggage | Wolfman Luggage

nothing new under the sun with saddle bags like this. To me they're all the same with all the same flaws. Most of these bags have the mounting strap sewn to the nearside of the bag. This put excessive stress on this stitch in a perpendicular direction. ATG is the only one that I know that worked around it. Wolfman is quality stuff generally though.

Luggage
 

To me its not a big deal because i always use a strap or two to lock them tight on the side rack.

I haven't used the Rocky Mountain bags personally, but my mates Nevil (here on the HUBB) and Jim both use them and they both like them, I was going to buy a set until the Canadian $ nose dived :( so I am still making do with the HT Mojave panniers, which are a bit too small for an extended trip.

In the past, some years ago, when finances were tighter for me than they are now I was heading off to Costa del Sol on the bike which at the time was an SV650S. I didn't have any luggage so I came up with an alternative. I bought 2 small identical black rucksacks, some velcro and some strong nylon fabic. I used the nylon fabric to create 2 straps that connected the rucksacks and lay across either side of the pillion seat. They were totally secure when on the bike, they held plenty of stuff, they were waterproof, had loads of outside pockets for bits and pieces and they looked absolutely fine and as good as any expensive kit. Plus, when off the bike I could use one as a normal rucksack as they were attached to the straps with caribiners.

Total cost approx £15, maybe £20, and I used them on quite a few trips.
I'm not a 'badge' fan but I like ingenuity and practicality. Seeing people pay 100's of pounds or dollars for soft luggage just makes me shake my head in disbelief. Each to their own I guess!