A lot of the beginning skaters at my rink start off on Ultima blades, and although some do move up to higher level blades, they for the most part, stick with the Ultima line.
My skate tech in the US, who is very well respected and knows his stuff highly recommends the ultima line for two reasons:
1) Most skaters eventually do move up to an 8' rocker, so the logic of just starting off there, thus eliminating the eventual transition does make some sense. (having said that, when you're at the level to switch to an advanced blade, that will likely have an 8' rocker, you're a good enough skater that the transition isn't that huge a deal).
2) Quality control. They do it. MK/Wilson do to, but much less so. He has been in the business a looooong time. He's been my skate tech since the 80's when I started skating competitively (and he was already well respected then), and is still in business. Over the course of his career he has seen some pretty messed up blades new in box, delivered from MK/Wilson. He showed me some Gold Seals (top of the line blade) that were so warped even I could see it. If you get warped blades, at best it's a pain in the bum, since you'll have to re-order and wait for the new ones to arrive. Ultima have a very strict quality control procedure, and I feel like he told me that warped ones just don't leave the factory. Nobody is perfect though.
He also points out that Ultima are cheaper, and they're just as good.
I tend to take his advice, so am very likely to switch to Ultima's next go around. Even factoring in shipping and customs charges to France, they're cheaper than the MK/Wilson lines. So, I'll just leave it there. But if you want to try the 7' rocker, why not? The only way to know anything for sure in this sport is to try it yourself. Professionals (MK) or Coronation Ace (Wilson) are the standard blades for someone who's a committed skater. They're both 7' rockers and will take you through your doubles. I skated on Professionals up until last year, when I decided to try out synchro blades. Like I said, if you're curious the only way to satisfy it is to give it a go.
You won't make a wrong decision here, so don't sweat it! Plus on the next pair of skates there will be another opportunity to try something else out.